Instructions for ISPACS 2003 Camera-Ready Manuscript Journal of Ultimate Research and Trends in Education ISSN: 2685-4252 (Online) and ISSN: 2685-0540 (Print) Vol. xx, No. xx, xxxx 20xx, pp: xx – xx DOI: https://doi.org/10.31849/utamax.vxxx Krashen's Monitor Model in L2 Acquisition: A Critical Review Mahmudul Hassan BGC Trust University Bangladesh, Chattogram, Bangladesh akib.cu@gmail.com ARTICLE HISTORY Received : 2022-08-25 Revised : 2022-11-13 Accepted : 2022-11-20 KEYWORDS Affective filter Critical evaluation Comprehensible input Second language acquisition Critical review ABSTRACT Stephen Krashen is well-known for a set of theories collectively known as the Monitor Model, which have made substantial contributions to the fields of language learning and writing. It is likely the most often quoted second language acquisition theory and has frequently dominated education discourse. Originally published around forty years ago, the Monitor Model contains a series of ideas which have evolved and are still debated today. Despite widespread criticism, the theory has had far-reaching effects on second language research and instruction since its inception. Controversies surrounding the Monitor Model propelled the discussion on what a theory of L2 acquisition ought to be. This paper evaluates Krashen's Monitor Model critically. It gives a thorough analysis of the model's underlying assumptions, explains each of the five hypotheses, and addresses objections to the theory based on relevant empirical evidence. It also evaluates some of Krashen's rebuttals to some of the objections made to his theories. The study reveals that despite the theoretical flaws, some of Krashen's fundamental assumptions appear to be valid. The research also concludes that Krashen's monitor model is still legitimate and relevant because its core concepts have survived in some form despite years of scathing criticism. 1. Introduction Beginning in the late 1960s, the study of second language acquisition (SLA) saw its first major advances in the 1970s (Ortega, 2007). A number of competing explanations for SLA have been proposed since then. Some have changed and continued to have an impact, while others have mostly fallen out of favor (VanPatten & Williams, 2015). Among them, Stephen Krashen's Monitor Theory, since its initial publication in 1977 and later modifications, has garnered both enthusiastic support and robust opposition. It was the first theory to be developed specifically for SLA. Its concepts have since formed the basis for significant developments in SLA theory. Krashen does not directly link Monitor Theory to Chomsky's theory of language, but the two seem to be related. Chomsky argues that humans possess a special faculty for learning new languages. This suggests that children's brains are pre-wired to process language, and all they need to learn a language is a stimulus in the form of input. According to Krashen, this process is also at work in second language acquisition. Krashen's monitor theory rests on the following five hypotheses: 1) The Acquisition Learning Hypothesis; 2) The Natural Order Hypothesis; 3) The Monitor Hypothesis; 4) The Input Hypothesis; and 5) The Affective Filter Hypothesis. Criticism by theorists and researchers, despite its popularity and significance, primarily for its definitional adequacy. Gitaski (1998) argues that Krashen's paradigm cannot be precisely defined or empirically examined. It may be appropriate to question the adequacy of Monitor Theory as having the explanatory capability in SLA for observable phenomena (Long, 1990; VanPatten, Keating, & Wulff, 2020). However, there are many in the academic community who dismiss Krashen's thesis and see his ideas as nothing more than historical footnotes. Gregg (1984) and others in the academic community have gone so far as to argue that it is not a cohesive theory and that the term "theory" is inappropriately applied to it. Krashen, however, vigorously refutes the counterevidence and insists that his theories stand and that the data backs up his claims. Is Krashen correct that his core principles hold true? Is it fair to generally dismiss Krashen's ideas? https://doi.org/10.31849/utamax.vxxx In this research, I will first briefly summarize Krashen's argument and then analyze its detractors' main points. Next, I will assess Krashen's interviews in which he responded to the criticisms of his work and show how he's right about some of the points he made. I will examine if Krashen is right when he asserts that his essential ideas have lasted and continue to be addressed, albeit under different names. I will also investigate where whether Krashen's key principles are true and still applicable to L2 learning. 2. Theoretical Background According to Liu (2015), SLA is commonly believed to be a field of study parallel to first language acquisition, hence discussing some of the findings from research on L1 acquisition is necessary for understanding theories of SLA, like Krashen's Monitor Theory. Krashen's five hypotheses are based on the idea that learning a second language is conceptually identical to learning a first language (Lai & Wei, 2019). Because Krashen's Monitor Model is influenced by Noam Chomsky's work on first language acquisition, it is important to discuss some of Chomsky's work here (Ellis, 1994). Krashen's hypothesis is one of the few that can coexist with Chomsky's view of language acquisition as a uniquely human capacity. In the '50s and '60s, Chomsky shook up the study of language by recasting it as a biologically grounded cognitive skill that is specific to humans. His work shifted the focus of linguistics from the outside to the inside of the human mind. A nativist perspective, which he developed, holds that some aspects of language and second- language acquisition are hardwired into human beings. According to this view, children are born knowing how to organize and understand the rudimentary rules and structures of a language. Furthermore, nativists hold the view that all children, regardless of their upbringing, possess a 'hardwired' ability to acquire a second language. In addition, these concepts form the basis of universal grammar, which every child is assumed to have access to (Lightbown and Spada, 2006, p. 15). The Universal Grammar (UG) theory proposes that despite their outward differences, all human languages share underlying similarities due to universal linguistic principles (Chomsky, 2000). In contrast to B.F. Skinner's behaviorist learning theories, nativism held that humans possessed no such innate tendencies. Behaviorists believed that children may pick up a language and other skills by mimicking and repeating their parents, which suggests that students could pick up a language by rehearsing and practicing the input they receive from others (Ellis, 2003; Skinner, 2005). For behaviorists like B. F. Skinner, who used environmental manipulation to teach animals new behaviors, this means that language is not a mental but rather a mechanical process (Politzer, 1961). However, nativists argue that acquiring a new language requires a complex cognitive process, and that repetition and imitation alone aren't enough because language acquisition happens so quickly (Chomsky, 1965). Even though it is still used today in the form of the Callan Method, Behaviorism was struck a fatal blow by Chomsky's (1959) scathing critique of Skinner's (1957) Verbal Behaviour (Entwistle, 2021). Chomsky (1959) claims that no precise assertion regarding the relative relevance of feedback from the environment is supported by either actual evidence or known reasoning. Because, as Chomsky (1965) argues, "A grammar of a language purports to be a description of the ideal speaker-hearer's intrinsic competence," he concluded that humans must have evolved to have certain linguistic information present from birth that helps children figure out the basic structures of language. His evidence is that children can construct correct sentences even when exposed to deficient language input (baby babble) and without any explicit instruction. Rather than simply repeating what they hear, they develop the ability to create entirely new sentences. In his analysis of second language acquisition, Stephen Krashen drew heavily on Chomsky's nativist theory. Chomsky's (1968) universal grammar (UG) and its application to second languages, as shown in Krashen's monitor model, are both considered examples of nativist theory (Brown, 2000; Lightbown & Spada, 2006; Liu 2015). During a time when behaviorist approaches to education were falling out of favor, Krashen's research was credited with helping to shape more contemporary approaches to language teaching, such as Communicative Language Teaching (Lightbown and Spada, 2006). 3. Krashen's Hypotheses 3.1 Acquisition vs Learning Hypothesis Krashen distinguished between “two distinct and independent ways of developing competence in a second language” (p. 10). The definition of acquisition states, “…language acquisition [is] a process similar, if not identical, to the way children develop ability in their first language. Language acquisition is a subconscious process… The result of language acquisition, acquired competence, is also subconscious” (1982, p. 10). He also suggests the names “natural learning”, “informal learning” and “implicit learning” to describe the process of acquisition. This method places an emphasis on natural communication, wherein speakers pay less attention to the structure of their utterances and more attention to the communicative act. Learning, which is the inverse of the acquisition system, is characterized as “conscious knowledge”, “knowing about the language”, “grammar”, “rules” or “explicit learning”. This method is the product of institutionalized schooling, and as a result, most people acquire a second language in a classroom setting. According to Krashen (1982), there is no connection between the two processes of learning and acquiring new knowledge; hence learning cannot become acquisition (Lai & Wei, 2019; Zafar, 2009). Krashen also hypothesizes that 'learning' is less important than 'acquisition'. The dichotomy between acquisition and learning came under heavy criticism. Gregg (1984) took issue with notions of "acquisition" as a path to competency, whereas "learning" is the ability to enunciate rules (Lichtman & VanPatten, 2021). Similarly, Cook (1993) notes that there is little evidence to support this distinction; hence, the contrast between acquisition and learning reads more like an assumption than a hypothesis. It's not always clear which parts of a language a person naturally knows and which ones they learnt (Gregg, 1984; McLaughlin, 1978). Because of this, it shouldn't be shocking that many people want Krashen's definitions of his theory to be more precise. Notwithstanding, Krashen continues to be unconcerned (McLaughlin, 1978, 1987). Another problem strongly related to Krashen's duality between acquisition and learning is that learning cannot convert into acquisition. Specifically, Krashen hypothesized that learned norms do not eventually become "internalized" as part of the learner's broad, abstract implicit linguistic system but instead are stored in the learner's Monitor and used only for revising their own output (Lichtman & VanPatten, 2021). This view contradicts the countless cases where L2 learners were expressly taught “rules” yet about which they were nonetheless able to build intuitions and native-like competency. In this context, Zafar (2009) cites the example of Polish-born author Joseph Conrad (1857-1924), who began studying English at the age of twenty-two and was subsequently accepted into the English canon the following decade. 3.2 The Natural Order Hypothesis Roger Brown showed in the 1960s that kids taught English as a first language exhibited "mastery" of a set of bound and unbound morphemes in English that followed a relatively constant pattern over time (Brown, 1973). Other researchers, such as Bailey et al. (1974), Dulay & Burt (1974), Krashen et al. (1977), and Larsen-Freeman (1975), also reported evidence of natural order from the outcomes of their research on morpheme orders. Based on a synthesis of the findings of this line of research, Krashen (1982, p.12) claimed that any person who learns a language would acquire that language in a specific, consistent pattern. This indicates that some language rules are acquired early on, while others are acquired later. For example, regardless of age, culture, or previous language knowledge, students studying English will first learn the plural form of a noun (e.g. students) before learning the third-person singular form of a verb. It has also been found that students are more likely to learn nouns before they learn the possessives of nouns (e.g. takes). In addition, the hypothesis states that the order of acquisition stays the same regardless of whether or not there is explicit instruction; to put it another way, the natural order of acquisition cannot be altered by teaching and learning that is done explicitly. Krashen, on the other hand, emphasizes that the relevance of the natural order hypothesis is not that a language program syllabus ought to be based on the order in which the studies were conducted. Krashen does not separate grammatical morphemes from other linguistic components like syntax or phonology; hence the Natural Order Hypothesis is in a precarious position due to a lack of data and support from morpheme studies. According to Gregg (1984), it is misleading to extrapolate from research on the acquisition of a small set of English morphemes to the study of second language acquisition as a whole. The notion that there is a natural order is predicated primarily on studies of the order of morphemes in English, which have already been shown to be insufficient (Gass & Selinker, 1994; McLaughlin, 1987). Critics Larsen-Freeman and Long (1991) also point out that the morpheme ordering isn't explained (Fry, 2018). Others have pointed to problems with the Bilingual Syntax Measure, the data collection tool utilized in morpheme research, as a possible explanation for the observed association (Fry, 2018; Hakuta & Cancino, 1977; Ellis, 1994). The concept also fails to account for cultural and linguistic differences among its potential subjects (Block, 2003, p.21). To give just one example, a learner of English as a second language whose first language is Bengali and another whose first language is German cannot take the same path to learn English grammatical structures. However, by the mid-to-late- 1980s, dozens of studies using a wide range of research methods had reported on the acquisition of English as a second language by learners of varying ages and with a wide range of first languages. The criticisms started to die down, and now morpheme orders are established as a fact in L2 acquisition, which means that they are no longer contested (Lichtman & VanPatten, 2021; Hawkins, 2019; Long, 1990). As a result, a theoretical explanation for such ordering is something that is being debated (Lichtman & VanPatten, 2021). 3.3. The Monitor Hypothesis The monitor hypothesis, which requires the use of formal rules or conscious learning, investigates the connection between learning and acquiring, in addition to the mutual influence that the two have on one another. The ability to initiate speech is unique to the acquisition, but learning can alter these expressions and affect how well they come across (Krashen, 1982). Planning, editing, and correcting are all tasks that fall under the purview of the Monitor, a cognitive process that necessitates the use of explicit rules or deliberate learning. The monitor stores the knowledge until the time comes when the learner is ready to put it to use. According to Krashen (1982, p. 15), the purpose of learning is to watch and change the utterances that are made while the process of acquisition is taking place. Moreover, according to the monitoring hypothesis, there are three prerequisites for the monitor to do its job properly (Krashen, 1999). The first requirement is adequate preparation time, during which the performer can choose and apply the necessary grammatical rules. Second, the performer should be thinking about the form rather than the meaning. The third requirement for the effective use of a language is familiarity with its grammatical rules and associated notions. The correct tense, rules of pluralization, the usage of articles (a the), etc., are only a few examples of grammatical concepts that students should be familiar with (Krashen & Terrell, 1983). Although these three components are necessary for monitoring to occur, they are not sufficient. Even if these prerequisites are met, performers may not apply the learned knowledge (Krashen, 1981). According to Krashen (1981), there are three types of monitor users: "over-users," "under-users," and "optimal users." Over-users use monitors too frequently. Their lack of confidence and tendency to constantly correct themselves prevents them from ever reaching true fluency in the target language. Since they are so concerned with the correctness and grammaticality of their words, they have trouble expressing themselves naturally. Under-users are those who do not employ conscious knowledge. Instead, they produce a phrase using intuition. They do not care about using the monitor or correcting their mistakes. Monitor under-users may have learned their language and rely primarily on this method out of personal preference or ignorance. Optimal users are those who use monitors appropriately. They strike a healthy balance between editing their own speech and speaking intuitively. To monitor language, knowledge of semantics, vocabulary, and grammar is required. The conscious learning that functions as a self-monitor can affect the output before or after a spoken or written speech (Krashen, 1982). The monitor evaluates student work for errors and ensures it is as error-free as it can be to serve as a mental accuracy-checking apparatus. The way in which students use the monitor might be incorrect, excessive, or suitable, depending on the degree of confidence they have in their ability to comprehend the material. When students want to communicate more freely, they use the monitor less. This means that accuracy suffers. Also, the simplicity of the knowledge learned is of the utmost importance, since monitoring seems to work best when the rules learned are easy to apply and not too complicated. The Monitor Hypothesis proposed by Krashen has likewise been criticized. Latifi et al. (2013) have provided a critique of the Monitor Hypothesis by highlighting the fact that "He relegates language monitoring to a peripheral position in language acquisition. It is seen as simply being a post-learning process, a tool for the use of language in certain conditions". McLaughlin (1987) is another researcher who was not a fan of the theory because of how difficult it was to provide evidence of Monitor use and how untestable it was. Gregg (1984) raises a similar criticism, emphasizing that Krashen ends up contradicting himself with the Acquisition-Learning Hypothesis in that he disregards the importance of comprehension by limiting the usage of the Monitor to 'learned' language, which only occurs in production. Another argument against the monitor model theory holds that, in everyday conversation, speakers just don't have the mental bandwidth to focus on the structure of their words and make minute adjustments as they go. If that were the case, our speech would slow down and sound a little weird due to all the pauses (Mitchell and Myles, 2004, p. 46; cited in Kamal, 2022). Under- and over-users, according to McLaughlin (1987), are terms that relate to the reality that different students have different levels of proficiency with a given grammatical rule and that it would be imprudent to provide credit for this variation to the monitor. Another criticism levelled at the hypothesis is that it fails to account for the role of the Monitor in the interpretation of statements, as argued by Kasap & Peterson (2018), "we often do not use the knowledge of grammar rules to understand certain phrases in a foreign language? Does not knowledge of certain morphological, syntactic, semantic, phonetic and/or contextual rules make it easier for us to understand unfamiliar words, for example? Krashen's theory does not consider these questions." In addition, it is difficult to tell if a student is monitoring the acquired system or the learned system (Mitchell & Myles, 2004). While Krashen restricts the Monitor to second-language learners, Fry (2018) raises the important topic of how it functions for first- language learners: "Does it exist? Are first language learners more efficient Monitor users? The restrictions Krashen places on the conditions on Monitor use for second language users might lead one to suggest second language learners need to use their Monitor more efficiently". 3.4 The Input Hypothesis The Input Hypothesis could be considered the most influential hypothesis in L2 acquisition, given that it attempts to address the question of how language is acquired. The utilization of "comprehensible input," which Krashen (1985) describes as the knowledge that learners already know in addition to the information that is one level higher, is what makes acquisition feasible, as stated by Krashen (1985). According to Krashen (1985, 1989), language cannot be learned through repeated repetition. Internal mechanisms, such as the learner's mental processing of linguistic elements in response to the input they were given, may also contribute to its acquisition. According to Krashen (1985, p. 2), the only way to acquire a foreign language is to either interpret messages or be exposed to input that is already simplified for the learner. In his theory, Krashen (1985) claims that the learner of a second language is left with a collection of words that are viewed as incomprehensible noise if the target language does not contain vocabulary that the second language learner can grasp, whether spoken or written. Similar to the Acquisition-Learning Hypothesis and the Natural Order Hypothesis, the Input Hypothesis emphasizes acquisition above learning (Zafar, 2009). Krashen (1985) hypothesized that the type of language that learners of the second language were exposed to has a significant role in determining how well they were able to acquire the target language. Listening and reading are two of the most effective ways for a learner to take in an input language that has a structure just beyond their current competence, as stated by Krashen (1981). Krashen refers to this concept as "i+1," where "i" stands for the learner's current level, and "1'' refers to the language features just a touch above that level. When evaluating the "1" part, all of the following factors will be taken into consideration: context, outside knowledge, and current competency (Lai & Wei, 2019). For a second- language learner at the "i" level, progress to the "1" level requires exposure to understandable material comprising the "i+1" structure (Krashen, 1985). Modifications to the level of "Comprehensible Input" are necessary when the child develops a more excellent command of the language. "we are able to understand language with the help of context, which includes extra-linguistic information, our knowledge of the world, and previously acquired linguistic competence," as Krashen (1985) put it. The theory's two implications are as follows: first, proficiency in communication through comprehensible input would emerge naturally rather than be taught; second, grammar is spontaneously learnt if "a sufficient amount of comprehensible input" is obtained. Krashen (1985) cited speech examples from a parent to a child, from an educator to a second language learner, and from a native speaker of the target language to a language acquirer as evidence to support the Input Hypothesis. The input hypothesis also posits that there will be a natural "silent period" while one is learning and acquiring a language but not yet creating any language because the learner is seeking to feel fluent in their newly acquired language before deploying it. In addition, Krashen's paradigm emphasizes the significance of diverse linguistic features for comprehensible input (Alahmadi, 2019). Though the Monitor Model has had a significant impact on the study of second language acquisition, its fourth hypothesis, that of input, has not been without criticism from other linguists and educators in the area. Krashen suggested that the only method to learn a language is by exposure to comprehensible input and that we never learn a language through being corrected, speaking, or studying. However, other studies have since disproven this. Another assertion made by Krashen (2010) is that the process of genuine language acquisition occurs involuntarily and is stored in the brain without our conscious knowledge. In her study of the Canadian immersion program, Swain (1985) demonstrated that the rate of acquisition was relatively stifled, despite the fact that learners were exposed to huge quantities of comprehensible input, which would seem to be the ideal setting according to the Monitor Model. Liu's (2015) study, which drew on the work of Berwick and Weinberg (1984), showed that a kid could learn the passive form of a verb by using existing syntactic or lexical knowledge without the aid of extra- linguistic or contextual knowledge. These studies collectively lead to the argument that comprehensible input is not the only component in an acquisition that plays a causal role. The successful acquisition of a foreign language depends on a variety of factors. The affective filter, for example, can restrict comprehensible input when the learner lacks motivation but permit it when the learner identifies with the target language community and is worried about failing to acquire the target language. The Comprehensible Input hypothesis proposed by Krashen has to be complemented by other theories due to the fact that it is still incomplete and was not adequately formulated. Since Krashen views input to be the only variable that can have an effect on second language learning, he assigns the learner's participation in the process a minor part in the overall acquisition of the second language (Brown, 2007). Long (1983) proposed the "Interaction Hypothesis" as a solution to this problem. This hypothesis endeavors to explain how comprehensible input can be produced most effectively, accepting the presumption that comprehensible input is the driving force behind language acquisition. Initially, Long proposed that input becomes comprehensible when students reflect on it and negotiate its meaning through contact with their peers. Later, Long (1996) developed the idea that the process of input modification and acquisition relies heavily on interaction and the negotiation of meaning between interlocutors and that interaction also provides learners with the chance to connect input and output. With his Comprehensible Output Hypothesis, Swain (1995) argued that output is just as crucial as input, if not more so. This suggests that, contrary to Krashen's beliefs, the learner's output plays a significant and autonomous part in the development of their communicative skill. Language output, which can include both verbal and written forms, can also help students identify areas of improvement and bridge gaps between their native language and the target language. Knowledge of this sort can help students learn more effectively, either by introducing them to new material or by assisting them to better retain the material they already know (Swain 1995). Schmidt (1990) proposed the Noticing Hypothesis, which contrasts with Krashen's theory by highlighting the significance of awareness and cognition in the learning process. Krashen did not provide a wholly transparent definition for Input Hypothesis, Formulation (i+1), or Next Level (i+1). McLaughlin (1987) believes that Krashen does not present evidence for the input hypothesis; rather, he only suggests that some facts might be understood from the perspective of this theory. This is McLaughlin's key argument against Krashen's research. Lightbown and Spada (2006), try to give a much broader interpretation, in which i represent "the level of knowledge already acquired", and +1 is a metaphor for language that is just a step beyond that level (Liu, 2015). McLaughlin (1987, cited in Liu, 2015) considers formulation (i+1) as an unknown structure. The authors Lightbown and Spada (2006) attempt to provide an alternative explanation. The method of determining the next level in the natural order further demonstrates the haziness of the notion (Liu, 2015). This is because determining the "natural order" of development makes it difficult to know which specific structure should be gained first. Caregiver speech is not less complex than adult speech, as shown by Newport et al. (1977) in areas such as clauses with deletion or movement of parts, inquiries, and imperatives. This finding doubts Krashen's (1985) hypothesis that simplified input, such as caretaker speech, will facilitate language acquisition (Gregg, 1984; Liu, 2015). Consistent with these findings, Heath (1983), who showed that black children from middle-class homes learned to talk at a far higher level than their own by imitating what they heard in the environment (McLaughlin, 1987; Liu, 2015). Krashen's assertion is further undermined by the findings of Gleitman et al. (1984), who reanalyzed the data published by Newport et al. (1977) and found that exposure to sophisticated maternal speech aids a child's language development (White, 1987; Liu, 2015). 3.5 The Affective Filter Hypothesis The fifth and final theory, the Affective Filter hypothesis, suggests that learners need more than just exposure to the target language and enough comprehensible input to succeed in learning a new language. Other factors, such as motivation, self- confidence, and anxiety, also play a role in the success of second-language learners. The filter has an effect on acquisition because it limits the available input and can be set to either "high" or "low." Learners are more likely to take in a sizable percentage or all of the input when their emotional filter is "low," as is the case when they are motivated, self-confident, and have low anxiety levels. On the other hand, second language acquisition may be hindered or prevented when the filter is "high", as exemplified by the context in which the learner feels uptight, self-conscious, or unmotivated (Krashen & Terrell, 1983). Some have questioned the validity of the Affective Filter Hypothesis on the grounds that it fails to provide a sufficient description of the breadth of the variables, the process by which an unmotivated learner eliminates information that is presented to them, or the manner in which the affective filter itself develops or functions (Gass & Selinker, 2008, p.403). Further, the claim that affective factors alone account for individual variation in second language acquisition has also been questioned. According to Krashen (1982), most adult language learners experience a "strengthening of the affective filter around puberty," but children's lack of this emotional filter allows them to more easily acquire the target language. However, differences in motivation, self- confidence, and anxiety across children, which are thought to account for child-adult disparities in second language acquisition, show that this argument cannot stand up to scrutiny (Latifi et al., 2013). In this context, McLaughlin (1987) provided evidence supporting the idea that learning a second language throughout one's adolescent years is optimal. Along the same line, Brown (2007) asserts that there are an unlimited number of instances in which adults have achieved native-like proficiency. This casts doubt on the hypothesis that an affective filter blocks out comprehensible input before it reaches the brain's language acquisition device. 4. Krashen's Response to His Critics It is evident from a review of Krashen's critics that the Monitor theory raises numerous questions. It was heavily attacked and disregarded by the majority of individuals. However, Krashen contends that his theories are here to stay and continue to be utilized under other terms. Following are discussions of some of Krashen's reactions to the criticisms of his theories, as well as references to support some of his commentary. Krashen's response to the complaint that the Input Hypothesis is too simplistic to adequately describe the complicated process of language acquisition is as follows: Some critics say, “No, it couldn’t be that simple. It must be more complicated.” Such statements are not arguments, but are statements of belief. I wonder if physicists reacted the same way when Einstein said e = mc2. Did they say, “It couldn’t be that simple, the formula must be much more complicated?” What matters, of course, is what the evidence says, not someone’s idea of how things should be (Latifi et el., 2013). In favor of Krashen, one could cite Ellidokuzolu (2008), who states, "Despite the fact that comprehensible input hypothesis is not explanatory enough, it does not mean that the theory is deficient, since Newton also did not provide enough detail concerning how gravity takes place.” Krashen responded to McLaughlin's (1990) criticism of his distinction between subconscious (acquisition) and conscious (learning) processes by stating, "Acquisition and learning are no more difficult to define empirically as their synonyms, implicit and explicit learning, terms that McLaughlin and other critics have no problem using" (Latifi et el., 2013). Bialystok (1979, referenced in Lichtman & VanPatton, 2021) offered an early concept of implicit versus explicit knowledge that resembles Krashen's notion of learning versus acquisition: “Those rules which can be consciously entertained by the learner are stored in ‘explicit knowledge’; those rules which are honoured without attention to the rule or even an ability to state it are stored in ‘implicit knowledge'." Similar to Krashen's assertion that learning cannot become acquisition, there is a growing consensus that explicit information cannot become implicit knowledge. (Rebuschat, 2015; Lichtman and VanPatten 2021). Krashen was asked in a 2016 interview with P'Rayan if his five theories were still relevant, and he responded: "…they have withstood the test of time – all published evidence remains consistent with the hypotheses." Scholars like Lichtman and VanPatten have conducted investigations backing up Krashen's assertion that his views have endured. The authors Lichtman and VanPatten (2021) evaluate the continued relevance of Stephen Krashen's early theories on L2 acquisition in light of subsequent empirical studies and theoretical development. They conclude that Krashen's ideas and frameworks are still relevant and applicable today since they have survived in some form or another, despite the fact that they are frequently unacknowledged and categorized using new terminology. They contend that three of Krashen's five hypotheses—the "Acquisition- Learning Distinction," "Natural Order," and "Input" hypotheses—continue to be useful today, despite having been reframed using concepts like "implicit versus explicit learning," "ordered development," and "a central role for communicatively embedded input" Lichtman and VanPatten (2021) argue that there is more support for the natural order hypothesis now than there was back in the '70s and '80s. Kurniawati (2021) provided evidence supporting the natural order concept by detailing how a polyglot benefited from her prior language learning when acquiring a new one. In addition, their findings show that language instructors commonly use the concept of "comprehensible input," despite the fact that the term itself is rarely used. Regarding the Input Hypothesis, White (1987) states, “there is something essentially correct about the input hypothesis”. In a similar vein, Jegerski (2021) argues that two of Krashen's central ideas continue to be valid and are so widely accepted that they are no longer associated with a particular theory. These ideas are the distinction between acquisition and learning, as well as the idea that acquisition occurs through the comprehension of input. In support of Krashen's thesis that only comprehensible input may contribute to the development of a learner's interlanguage system, Schwartz (1993) and Zobl (1995) cited fresh research on the consequences of giving learners explicit positive and negative information. Researchers such as Rubin (1975) have recognized monitoring as an essential component of the learning process. In addition, Ellis (2003) defines monitoring as one of the five fundamental components necessary for successful language acquisition. In her study, Jegerski (2021) provides two explanations for the research procedures utilized in language processing research, and links these justifications back to Monitor Theory components. Chen (2022) thinks that the affective filter hypothesis is among the most cutting-edge research areas in Krashen's SLA theory. In her research, Kurniawati (2021) demonstrates that affective variables such as motivation, self-confidence, anxiety, and personality traits play a significant impact in a second language learner's performance. Regarding Swain's (1985) assertion that outut generation is at least as significant as input, if not more so, Krashen opines: "Swain’s evidence is not convincing to me. Swain only noted that children in French immersion classes after many years were not perfect in French and didn’t talk much in class and concluded that output was a major factor in acquisition. I have argued that the reason French immersion students aren’t even better than they are, is a lack of certain kinds of input: They don’t do pleasure reading in French and they don’t interact with peers in French. The Comprehension Hypothesis predicts that the problem is lack of input, not lack of output (Latifi et el., 2013)." Krashen was questioned by Latifi et al. (2013) about the students for whom the "quiet period" lasts indefinitely. Krashen retorted with: We don’t have any cases of lifetime silent periods with normal language acquirers. What we have are cases in which the silent period lasts longer than some people expect it to last, those unfamiliar with the language acquisition process and whose expectations are based only on their own beliefs and very limited observations. P'Rayan (2016) questioned Krashen on the criticism that he has updated his Monitor Model and the manner in which second-language learners absorb the language numerous times since 1977. His response was: The revisions I have made are not fundamental changes but expansions: The hypotheses were originally intended to explain phenomena in adult second language acquisition, but we have found that they help explain what is going on in child second language, first language, literacy development (eg Krashen 2004), and to some extent even animal language (Krashen, 2013). 5. Conclusion In this study, I have elucidated the Monitor Model's fundamental ideas and concepts in detail. Before evaluating Krashen's comments critically, I have also described the controversies surrounding the Monitor Model and Krashen's responses to them. Concerning the subject of whether the core principles behind the five components of Krashen's Monitor Model are still valid, I have demonstrated that they have withstood the scrutiny and hence cannot be discredited. From the analysis of Krashen's Monitor Model, it is obvious that the theory poses various concerns. Certainly, there are problems with his hypothesis, but Krashen has also taken more than his share of flak. Despite the severe criticism of Krashen's ideas, many of them have grown through additions and refinements to survive. As some academics would have us believe, Krashen's Monitor Theory's central ideas have not fully disappeared. These concepts are still relevant and are resurfacing under other names, frequently without recognition. Based on recent advancements in L2 research and the recent efforts of academics such as Lichtman & VanPatten and others referenced in this publication, it is obvious that fundamental notions concerning L2 acquisition today can be traced back to Krashen's seminal 1970s work. In several instances, his theory's hypotheses cannot be tested due to a lack of empirical evidence and ambiguous term definitions. These limitations, while frustrating, have also spurred other academics to find better solutions to the issues raised, hastening the advancement of theories concerning second language learning. Controversies surrounding Monitor Theory's sufficiency have prompted discussions on the nature of an appropriate theory of L2 acquisition (Lichtman & VanPatten, 2021; Jordan, 2004; Long, 1990; McLaughlin, 1987; Gregg, 1984). Although Krashen's theory first appeared over 40 years ago, its adaptability is perhaps its greatest strength. "The changes are additions and expansions. I can’t think of any place in which any of the original hypotheses were wrong. (1) I added the “output filter” to deal with cases in which people do not perform as well as they could,'' Krashen notes (Latifi et el., 2013). Last but not least, it appears that the Monitor theory is not flawless because it has some shortcomings; yet, it is a very systematic and thorough theory because its core principles are still correct. Krashen, when asked to comment on his overall perception of his theory, stated, "I think it’s a good theory. ‘Good’ does not necessarily mean ‘correct.’ ‘Good’ means that in testing hypotheses that make up the theory, we make progress" (Latifi et el., 2013). References Alahmadi, N. S. (2019). The role of input in second language acquisition: An overview of four theories. Bulletin of Advanced English Studies, 3(2). 70-78 Bailey, N., Madden, C., & Krashen, S. D. (1974). Is there a "Natural sequence” in adult second language learning? Language Learning, 24(2), 235-243. https://doi.org/10.1111/j.1467- 1770.1974.tb00505.x Berwick, R.C., & Weinberg, A.S. (1984). The grammatical basis of linguistic performance. Cambridge, MA: MIT Press. Bialystok, E. (1979). Explicit and implicit judgements of L2 grammaticality. Language Learning, 29(1), 81-103. https://doi.org/10.1111/j.1467- 1770.1979.tb01053.x Block, D. (2003). The social turn in second language acquisition. Edinburgh University Press. Brown, H. D. (2007). Principles of language learning and teaching (5th ed.). Addison Wesley Longman. Brown, H. D. (2000). Principles of language learning and teaching (4th ed.). White Plains, NY: Addison Wesley Longman, Inc. Brown, R. (1973). A first language: The early stages. Harvard University Press. http://dx.doi.org/10.4159/harvard.978067473246 9 Chen, Y. Y. (2022). A review of research on Krashen’s SLA theory based on WOS database (1974-2021). Creative Education, 13(7), 2147- 2156. https://doi.org/10.4236/ce.2022.137135 Chomsky, N. (2000). New horizons in the study of language and mind. Cambridge University Press. Chomsky, N. (1968). Language and the mind. Harper and Row. https://doi.org/10.1037/e400082009- 004 Chomsky, N. (1965). Aspect of the theory of syntax. MIT press. Chomsky, N. (1959). Review of verbal behavior by B F Skinner. Language 35(1), 26-58. https://doi.org/10.2307/411334 Chomsky, N. (1957). Syntactic structures. De Gruyter Mouton. https://doi.org/10.1515/9783112316009 Cook, V. (1993). Linguistics and second language acquisition. Macmillan. https://doi.org/10.1007/978-1-349-22853-9 Dulay, H., & Burt, M. (1974). Natural sequences in child second language acquisition. Language Learning, 24(1), 37-53. https://doi.org/10.1111/j.1467- 1770.1974.tb00234.x Ellidokuzoglu, H. (2008). Beyond the monitor model. International Journal of Foreign Language Teaching, 4(1), 6–18. Ellis, R. (2003). Task-based language learning and teaching. Oxford University Press. Ellis, R. (1994). The study of second language acquisition (Oxford Applied Linguistics). Oxford University Press. Entwistle, T. (2021). The monitor model: A critique of its concepts and impact. Korea TESOL Journal, 16(2), 127-138. Fry, C. (2018). Second language acquisition - Krashen and his critics. University Study Document - Anth 6800. California State University. Gass, S. M., & Selinker, L. (1994). Second language acquisition: An introductory course. Lawrence Erlbaum Associates Publishers. Gass, S. M., & Selinker, L. (2008). Second language acquisition: An introductory course (3rd ed.). Routledge. Gitsaki, C. (1998). Second language acquisition theories: Overview and evaluation. Journal of Communication and International Studies, 4(2), 89-98. Gleitman, L. R., Newport, E. L., & Gleitman, H. (1984). The current status of the motherese hypothesis. Journal of Child Language, 11(1), 43-79. https://doi.org/10.1017/s0305000900005584 Gregg, K. R. (1984). Krashen's monitor and Occam's razor. Applied linguistics, 5 (2), 79-100. https://doi.org/10.1093/applin/5.2.79 Hakuta, K., & Cancino, H. (1977). Trends in second- language-acquisition research. Harvard Educational Review, 47(3), 294-316. https://doi.org/10.17763/haer.47.3.e03v062m647 45872 Hawkins, R. (2019). How second languages are learned. Cambridge University Press. Heath, S. B. (1983). Ways with words: Language, life and work in communities and classrooms. Cambridge University Press. https://doi.org/10.1017/cbo9780511841057 Jegerski, J. (2021). Krashen and second language processing. Foreign Language Annals, 51, 318- 323. https://doi.org/10.1111/flan.12557 Jordan, G. (2004). Theory construction in second language acquisition. John Benjamins Publishing. https://doi.org/10.1075/lllt.8 Kamal, A. (2022). Critical appraisement of Monitor Model. Research Journal in Advanced Humanities, 3(1). 64-74. https://doi.org/10.58256/rjah.v3i1.766 Kasap, S., & Peterson, R. (2018). An interview on the role of input in second language learning. Learning Journal of Education and Practice, 9(13), 81-87. Krashen, S. (2010). The Goodman-Smith hypothesis, the input hypothesis, the comprehension hypothesis and the (even stronger) case for free voluntary reading. In P. Anders (Ed.), Defying convention, inventing the future in literacy research and practice: Essays in tribute to Ken and Yetta Goodman (pp. 56–99). Routledge. Krashen, S. D. (1999). Seeking a role for grammar. A review of some recent studies. Foreign Language Annals, 32, 245-254. https://doi.org/10.1111/j.1944- 9720.1999.tb02395 Krashen, S. (1985). The input hypothesis: Issues and implications. Laredo Publishing Company. Krashen, S. D., & Terrell, T. D. (1983). The natural approach: Language acquisition in the classroom. Prentice Hall International English Language Teaching. Krashen, S. (1982). Principle and practice in second language acquisition. Pergamon Press. Krashen, S. (1981). Second language acquisition and second language learning. Pergamon Press. Krashen, S., Houck, N., Giunchi, P., Bode, S., Birnbaum, R., & Strei, G. (1977). Difficulty order for grammatical morphemes for adult 2nd language performers using free speech. Tesol Quarterly, 11(3), 338-341. Kurniawati, N. (2021). Understanding Krashen hypothesis of second language acquisition: A case study of a polyglot. International Journal of Language Education and Culture Review, 7(1), 83-89. https://doi.org/10.21009/IJLECR.071.08 Lai, W., & Wei, L. (2019). A critical evaluation of Krashen’s monitor model. Theory and Practice in Language Studies, 9(11), 1459-1464. https://doi.org/10.17507/tpls.0911.13 Larsen-Freeman, D., & Long, M. (1991). An introduction to second language acquisition research. Longman. Larsen‐Freeman, D. (1975). The acquisition of grammatical morphemes by adult ESL students. TESOL Quarterly, 9(4), 409–430. Latifi, M., Ketabi, S., & Mohammadi, E. (2013). The comprehension hypothesis today: An interview with Stephen Krashen. Electronic Journal of Foreign Language Teaching, 10(2), 221-233. Lichtman, K., & VanPatten, B. (2021). Was Krashen right? Forty years later. Foreign Language Annals, 54(2), 283-305. https://doi.org/10.1111/flan.12552 Lightbown, P. M., & Spada, N. (2006). How languages are learned (3rd ed.). Oxford University. Liu, D. (2015). A critical review of Krashen’s input hypothesis: Three major arguments. Journal of Education and Human Development, 4(4), 139– 146. doi:10.15640/jehd.v4n4a16 Long, M. H. (1996). The role of the linguistic environment in second language acquisition. Handbook of Second Language Acquisition, 2, 413-468. https://doi.org/10.1016/b978- 012589042-7/50015-3 Long, M. H. (1990). The least a second language acquisition theory needs to explain. TESOL Quarterly, 24(4), 649-666. https://doi.org/10.2307/3587113 Long, M. H. (1983). Linguistic and conversational adjustments to non-native speakers. Studies in Second Language Acquisition, 5(2), 177-193. https://doi.org/10.1017/s0272263100004848 McLaughlin, B. (1990). “Conscious” versus “Unconscious” learning. TESOL Quarterly, 24(4), 617–634. https://doi.org/10.2307/3587111 McLaughlin, B. (1987). Theories of second language learning. Edward Arnold. McLaughlin, B. (1978). The monitor model: Some methodological considerations. Language Learning, 28(2), 309-332. https://doi.org/10.1111/j.1467- 1770.1978.tb00137.x Mitchell, R., & Myles, F. (2004). Second language learning theories (2nd ed.). Arnold. Newport, E., Gleitman, H., & Gleitman, L. (1977). Mother, I’d rather do it myself: Some effects and non-effects of maternal speech style. In C. E. Snow & C. A. Ferguson (Eds.), Talking to children (pp. 109–149). Cambridge University Press. Ortega, L. (2007). Second language learning explained? SLA across nine contemporary theories. In B. VanPatten, & J. William (Eds.), Theories in second language acquisition: An introduction (pp. 245-272). Lawrence Erlbaum Associates. P'Rayan, A. (2016). One on one interview with Professor Stephen Krashen. The Journal of English Language Teaching (India), 2(5), 31-34. Politzer, R. (1961). Teaching French: An introduction to applied linguistics. Ginn. Rebuschat, P. (Ed.). (2015). Implicit and explicit learning of languages (Vol. 48). John Benjamins Publishing Company. . https://doi.org/10.1075/sibil.48.003int Rubin, J. (1975). What the "Good language learner" can teach us. TESOL Quarterly, 9(1), 41-51. https://doi.org/10.2307/3586011 Skinner, B. F. (2005). Science and human behavior. Pearson Education. Skinner, B. F. (1957). Verbal behavior. Appleton- Century-Crofts. https://doi.org/10.1037/11256- 000 Schmidt, R. W. (1990). The role of consciousness in second language learning. Applied Linguistics, 11(2), 129-158. https://doi.org/10.1093/applin/11.2.129 Schwartz, B. D. (1993). On explicit and negative data effecting and affecting competence and linguistic behavior. Studies in Second Language Acquisition, 15(2), 147-163. https://doi.org/10.1017/s0272263100011931 Swain, M. (1995). Three functions of output in second language learning. In G. Cook, & B. Seidlhofer (Eds.), Principle and practice in applied linguistics: Studies in honour of H. G. Widdowson (pp. 125-144). Oxford University Press. Swain, M. (1985). Communicative competence: Some roles of comprehensible input and comprehensible output in its development. In S. Gass & C. Madden (Eds.), Input in second language acquisition (pp. 235–253). Rowley, MA: Newbury House. VanPatten, B., Keating, G. D., & Wulff, S. (2020). Theories in second language acquisition (3rd ed.). Routledge. VanPatten, B., & Williams, J. (2015). Early theories in SLA. In B. VanPatten & J. Williams (Eds.), Theories in second language acquisition: An introduction (2nd ed., pp. 17–35). Routledge.