The term input is a focal point in understanding Krashen’s Comprehensible Input Hypothesis. In language learning the concept of input as summarized by Gass (1997,p.1) “is perhaps the single most important concept of second language acquisition (SLA). It is trivial to point out that no individual can learn a second language (L2) without input of some sort”. The term input in language learning, as Richards; Schmidt (1992) defined, is the language that learners hear or receive which consequently triggers learning ( cited in Chioukh, 2011).Therefore, input is essential for language acquisition .
The concept of input has been approached differently according to three scope of views: The behaviorists regard language learning as governed by the stimuli and reinforcement learners are supposed to be exposed to and to receive. The mentalists, from their view as the name suggest, focus on the learners’s brain or ‘black box’. In order for a second language acquisition to occur, learners must be acquainted with input with a set of internal mechanism in order for L2 data to process (Ellis, 1985).
They stress on the fact that the brain’s readiness to learn language with a minimal exposure to input help to trigger acquisition (Ellis, 1997 cited in Zhang, 2009). In contrast, the interactionist stipulate that both linguistic environment and the learners’ inner mechanism in interaction activities, i.e. both input and internal language processing, are required for language learning (Zhang, 2009).
In here, Krashen claims that in order for a second language learning to occur, input must be exposed in a comprehensible manner, i.e., ‘comprehensible input’. This evokes the idea that language is best acquired when input is comprehended or understood at a level that can be slightly beyond the current level of competence. Krashen’s input hypothesis has been regarded as one of the substantial contributions to understand language learning process. Krashen , in his input hypothesis, concedes that “We move from i, our current level, to i+1, the next level along the natural order, by understanding input containing i+1” (Krashen, 1985, p.2)
In this sense, Gass explained that “the input a learner is exposed to must be at the i + 1 level in order for it to be of use in terms of acquisition” (Gass , 2011, p. 309). The main argument made by Krashen in his Comprehensible Input hypothesis is that comprehensible input leads to acquisition of L2 as learners are given access to the next level “i+1” because it leads them to understand and express meaning.
For example , if learners have a current level or competence “i” the next level in the developmental sequence is comprehensible input “i+1”.
Input Hypothesis claims that there are two corollaries (Krashen, 1985:
2). First, speaking is regarded as a result of acquisition and not its cause since it is a result of building competence via comprehensible input and cannot be taught directly. Second, grammar is automatically acquired if there is enough of input that is understood ( Cited in Gass , 2011 ).
According to Gass (2011), the’Language Acquisition Device’assumed by Krashen expressed by innate mental structure is activated by input at “i + 1” level which helps in altering a learner’s grammar. The acquisition then is conditioned by input. According to Krashen , the Input Hypothesis has important implications for the classroom. This is enhanced by the idea that exposure to input that is comprehensible is necessary and sufficient for the occurrence of second language learning.
Central to Krashen’s input hypothesis is comprehensible input which is necessary for all of acquisition. Teachers by providing learners with different materials such as listening and reading make input comprehensible for them. Besides, contextual information helps also to make input comprehensible and thereby acquiring the unknown structures (Krashen 1985, p.2).
Krashen (1982) made a distinction between implicit acquisition and explicit learning of L2 and argued that both involve separate mental processes and storage (Cited in Ellis, 2008). He states that in order to facilitate access to “comprehensible input” for learners, teachers should instruct them implicit knowledge.
The importance of Krashen’ input hypothesis leads to other major contributions as summarised by Liu (2015). It gives prominence to input as well as learners’ exposure to input (White, 1987 ); the emphasis is on the
message rather than form which gives rise to meaningful communication in the classroom (Brown, 2000); it gives prominence to communicative language teaching (CLT) approach rather than the previous rule- or grammar-based approaches (McLaughlin, 1987 cited in Liu, 2015).
Besides, the way input affects the process of languages acquisition has been viewed in accordance with four major hypothesis (Ellis, 1994 cited in Trawinski, 2005 ). As summarised by Trawinski (2005), these four major hypotheses are:
1-frequency hypothesis (the order of language acquisition is determined by the frequency of different items in the input: the more frequently an item occurs, the earlier it appears in learner’s output).
2-comprehensible input hypothesis (only comprehensible input leads to language acquisitions, incomprehensible input is neglected by the learner — cf. Krashen’s Monitor Model, Chapter VI).
3-output hypothesis (for input to be internalised the learner needs to use the new language form in a meaningful situation; only a form successfully produced by the learner becomes a part of his/her linguistic repertoire).
4-collaborative discourse hypothesis (learning how to participate in conversations leads from the memorisation of formulaic speech to the gradual acquisition of language structures).
Implicit acquisition of a second language for adults is limited because an additional input is required, under explicit learning framework in classroom situations, in order to achieve second language accuracy. The idea of consciousness is central in the explicit/ implicit distinction. Implicit acquisition is subconsciously processed which results in the knowledge of language. Explicit learning, in the other hand is consciously processed which results in knowing about the rules of the language. According to Ellis, explicit knowledge in SLA research “is generally used to refer to knowledge that is available to the learner as a con¬scious representation”( Ellis ,2008, p.355).
Earlier than the other researchers, Corder (1967) claimed that intake should be associated with language learning processing. He considers intake as what is internalized by the learner whereas input is what is available to the learner (Corder, 1967). According to Tavakoli(2012), Corder considers intake to be distinct from input, “which is the language that learners are exposed to” (p.176) whereas intake is “what they actually ‘take in'” (p.176) . This means that input will not contribute alone in the language acquisition because learners, while internalizing the language being learned, they contribute in making it part of their inter language system. Also, in order for input to be comprehensible, learners must notice the forms to be acquired (Schmidt, 1994) which means that comprehensible input must become intake. The latter requires also from the learner to assimilate the data and use it to promote IL development (Larsen-Freeman ; Long, 2014).
According to other models, intake refers to a process or a product. Tavakoli (2012, pp.176-177) reports that in the product view, intake is “unprocessed language input” and considered as “a sub-set of input before the input is processed by learners” ; according to the process view, it is “processed language input” and considered as “the process of assimilating linguistic data or the mental activity that mediates between the input ‘out there’ and the competence ‘inside the learner’s head”. The two different models can be presented according to the two following figures:
Figure I.1. Input, output: The product view (source: Tavakoli ,2012, p.177)
Figure I.2. Input, intake, output: The process view (source: Tavakoli ,2012, p.177)
Schmidt (1990; 1995; 2001) from his view, stated that both noticing and
understanding are two essential levels of awareness. As far as noticing is concerned, it is a necessary condition to facilitate intake and it must be associated with attention which is necessary for intake too. Schmidt (1993) considers attention as responsible for noticing and “the necessary and sufficient condition for the conversion of input into intake” (Schmidt, 1993, p. 209). Understanding as a second level of awareness, is the outcome of deeper learning.
He argues for “A more balanced view of the second language learning process” McLaughlin (1987, p. 51 , as cited in Liu, 2015 ). For Gregg (1984, p.90), the Input Hypothesis is totally rejected because it lucks “more explanatory power…”( cited in Liu, 2015). In the same line other researchers, such as Harley ; Hart, 1997; Harley ; Swain, 1984, suggested that though necessary for language acquisition comprehensible input alone is insufficient. Tavakoli (2012) celebrates the fact that the vagueness in Krashen’s definition “of what constitutes conscious versus subconscious processes, as they are very difficult to test in practice: How can we tell when a learner’s production is the result of a conscious process and when it is not?”(p. 11) is a reason for criticizing his hypothesis. However, Input Hypothesis like other hypotheses in the Monitor Model has been criticised by researchers. For example, McLaughlin (1987) argues that the evidence for Karashen’s hypotheis is not sufficient because there are only “assertions that have only tangential relevance to the central claims of the theory” (McLaughlin 1987 , p.43 cited in Liu, 2015). Therefore, he calls for an equilibrium between the internal and external factors, comprehension and production .
Second, the simplification of input argued by Krashen (1985) when he claimed that input can be made comprehensible by simplifying it; for example, caretaker speech (CS) directed at children who are acquiring their L1 and simplified somehow for communication, will facilitate language acquisition . This postulation can be critisised on two levels: “first, in L1 acquisition, CS does not always mean simplified speech; second, “comprehensible” input does not necessarily mean “simplified” or “caretaker speech” (Liu, 2015, p. 143).
Third, Krashen’s Input Hypothesis , which is part of the Monitor Model “an overall theory” as it was claimed by Krashen’s (1985, p.1), has been over-emphasised as “the central part” of his “overall theory”. Krashen’s (1980, p.168) overclaim of the Input Hypothesis to be “the single most important concept” is motivated by its attempt at “answer the critical question of how we acquire language” (see Liu, 2015, as cited in McLaughlin, 1987, p.36). Besides, Krashen’s (1985, p.4) claim that “All other factors thought to encourage or cause second-language acquisition work only when they contribute to comprehensible input and/or a low affective filter” seems to be over-emphasised to consider comprehensible input as the single causal factor in SLA. This overclaim can be refuted due to the contribution of other internal and external factors.
Liu (2015) states that the internal factors can be justified by the fact, as White (1987, p.98) points out, that “there may be more than one potential route for grammar change”. In here, White refers to other mechanisms underlying L1 and L2 acquisition such as the example from Berwick and Weinberg (1984) of the passive form acquired by the child. Their example underscores the fact that, apart from comprehensible input, the acquisition is based on the child’s existing syntactic or lexical knowledge and not on any contextual or extra-linguistic information ( cited in Liu, 2015) .
Liu (2015) claims that there are three major arguments about the Input Hypothesis. First, vagueness of the input hypothesis at three levels: comprehensible input, the next level (i+1), and the acquisition process . For instance, “the ambiguity is chiefly manifested in what the formulation i+1 signifies and what “comprehensible input” means”, and the decision on how the next level and what structure to be acquired first and what next along the natural order are not well determined. Besides, the acquisition process is “equally obscure” (Liu, 2015, p. 142).
As stated by Liu (2015), the external factors such as those of interaction hypothesis (Long, 1983, 1996), output hypothesis(Swain, 2000), noticing hypothesis (Schmidt, 1990), input processing (Vanpatten & Cadierno, 1993); apart from comprehensible input under the framework of Input Hypothesis, can enhance the successful acquisition. Long’s (1983) proposition of “modified interaction” in his Interaction Hypothesis such as strategies, tactics, and both is one way for language acquisition. Long’s (1996) view of corrective feedback and negotiation of meaning in interaction as stated by (Lightbown & Spada ( 2006, p.44) is another way for language acquisition (see Liu, 2015). Swain’s comprehensible output hypothesis supplements the external factors of language acquisition mainly through deeper processing of language, promoting “noticing” in language production and conveying meaning (Liu, 2015).
Long’s Interaction Hypothesis (HI) (1983b, 1983c, 1996) argues that developing language proficiency through comprehensible input is necessary but needs to be supported by interaction and communication. The importance of comprehensible input is undeniable, and, according to Long, “it is most effective when it is modified through the negotiation of meaning” (Ellis, 1997, p.47). Thus, the language used in classroom should be treated as interaction which serve in turn to provide opportunities for learning. The central aim of the hypothesis lies also on the focus on form as well as focus on meaning and that “interaction in the L2 furthers acquisition as well as the exchange of information” (Tavakoli ,2012, p.183).
Other researchers such as Schmidt and Frota (1986), Schmidt (1990, 1993, 1994), and Kormos (2001) consider noticing or “apperceiving” (Gass 1988, 1997) new language forms in the input by adult SL learners as a conscious process required for learning , in contrast to Krashen (1985, 1989) and Van Patten (1988) view of learning as a sub-conscious process. In the same line, Doughty (1991); Sharwood-Smith (1991, 1993) provided a theoretical and empirical framework on enhanced input that is based more on form and meaning rather than a focus on grammatical forms.
Negotiation for meaning also sustains interactants in a co-operative
manner to “develop mutual understanding as they work together to overcome communication breakdown” (Oliver, 2009, p. 137). “negotiation of meaning” offered SLA researchers to conceptualized input obtained via interaction (Long, 1983b; ?ahin, 2009; Swain, 2005; Swain & Lapkin, 1995, 1998) and enables learners “to transform what is initially incomprehensible to them into comprehensible input” (e.g., Pica, 1987a, 1992; Varonis & Gass, 1985, cited in Oliver, 2009, p. 137 ). Long considers interaction central in rendering learners actively engaged in order to acquire new language, for they need not to be only recipients of i+1.
Researchers have conceptualized “comprehensible input” with an access to input obtained via interaction and consider language competence as a result of interaction between a learner’s input and output (Krashen, 1981, cited in Gass ; Varonis, 1994; Lantolf ; Thorne, 2006; Long, 1991a, 1991b, 1996). In this sense, interaction refers to “communication among individuals, particularly when they are “negotiating meaning” or working to prevent a breakdown in communication” (Gass, 1997; Gass ; Mackey, 2000; Long, 1991a, 1991b; Pica, Doughty, ; Young, 1986, cited in Palma, 2014, p.2 ).
(Van Lier,1988) considers interaction as a medium between input
and intake. This can be clearly conceived with the application of interaction through meaningful activities. According to Figure this enables the cognitive process to occur in combination with the available input or sections ( cited in Xiao-yan, 2006).
Figure The role of interaction (Van Lier,1988, p.93) (source: Xiao-yan, 2006, p.28).
Long’s main contribution suggests that interactional adjustments make input comprehensible, and comprehensible input promotes acquisition, thus interactional adjustments promote acquisition (Lightbown and Spada, 1993, p.30). Based on his investigation of conversations between a native speaker (NS) or more competent interlocutor and non-native speaker (NNS), Long (1983) suggested his interaction hypothesis. In here with a consideration of Long’s theory to be endowed with a “cognitive perspective on second language learning” (Shane, 2015, p. 43), conversation is regarded as a medium by which the language knowledge subject of learning is acquired “with knowledge being a process of internalization, rather than a display of interactional competence and the ability to enter into social relations” (Shane, 2015, p. 43).
Long’s approach is also supported by the role of negotiation in social interaction. In this respect, Long (1996) claims that “negotiation work that triggers interactional adjustments by the NS or more competent interlocutor, facilitates acquisition because it connects input, internal learner capacities, particularly selective attention, and output in productive ways” (Long 1996, pp. 451-452). Negotiation of meaning occurs during communication breakdown and interactional trouble. Negotiation of meaning implies modification and restructuring of interaction when learners face difficulties in message comprehensibility (Pica, 1994). Thus, central to negotiation of meaning, when a communication problem occurs, there is an interactional work and adjustments done by interactants, to achieve mutual understanding. The aim of negotiation under a framework of intersubjectivity is to create a shared social world between interlocutors (Brooks, 2009).
Negotiation of meaning as studied by Pica, Young, and Doughty (1987) has a positive effect on comprehension especially through interactional modifications of input rather than linguistically simplifying input that is considered more conventional.
(cited in Petkova, Mariana,2009). In this regard, negotiation of meaning, is conceptualised as Long (1996) argues that negotiation of meaning helps learners to develop a second language acquisition through interactive tasks. He suggested also that the more heavily interaction is modified, the better input the learner will be (Long, 1996). Negotiation serves also to make input more comprehensible to the learner, and “facilitates acquisition because it connects input, internal learner capacities, particularly selective attention, and output in productive ways” (Palma, 2014, p.2).
“the interactive work done by interlocutors in order to ward off or resolve communication breakdowns which take place when the speaker’s utterance is not clear or comprehensible to the listener. In such situations, the impending or existing communicative impasse is signaled by means of clarification requests, confirmation checks, comprehension checks and repetitions, which leads to interactional modifications involving simplification or elaboration of the initial message, thus making input comprehensible” (Pawlak, 2014, p.53).
Third, a response is expressed as the attempt to repair the problem by the first speaker. Fourth, a reaction comes as a response or an extension to the repair or correction.
In this sense, Gourlay (2005) and Harris (2005) maintain that negotiation of meaning activates the students selective attention and interpersonal communication through the task-based approach “when students signal incomprehension about a lexical, morphological or complexity task item, a response from the other interlocutor is given trying to fill the gap . . . conversational turns later the item is acquired by the speaker who asked for clarification by using it abundantly through the entire act speeches of the following turns” (Gourlay, 2005, p. 115, cited in Palma, 2014, p.). Doughty and Pica (1986) proposed the negotiation model that is based essentially on the negotiation sequences which comprises “the opportunity that is provided to the learner to process utterances in the L2 which become more comprehensible” (p. 43). As cited in Palma (2014) the negotiation model integrates four components: First, a trigger which is “an utterance or part of an utterance that is not understood” (Doughty and Pica, 1986, p. 48). Second, a signal which is used when there is a lack of comprehension.
Based on conversational interaction, language acquisition is facilitated because “it connects input; internal learner capacities, particularly selective attention; and output in productive ways” (Long, 1996, pp. 451- 452). In here, conversational and linguistic modifications that occur in interaction together further comprehensible linguistic input. In this sense, a key point in understanding long’s interaction hypothesis is the learners’ exposition to modified input and the way interactants engage in conversation with learners.
Confirmation checks are used by the listener with expressions that often
involve repetition accompanied by rising intonation. Unlike the first strategy, Confirmation checks are used to confirm that what has just been said is correctly heard. Comprehension checks are strategies used by the speaker to check that the preceding utterance was understood by the listener and may also involve self repetition associated with rising intonation . They are often astablished in the form of a question (e.g., “Do you understand?”). Self-repetition is a strategy used by the speaker and may include partial, exact, and expanded repetitions of lexical items (Oliver, 2009 ). Ellis (2005) has identified negotiation sequences as clarification requests, confirmation checks, recasts, etc. Besides, negotiation research has been conceptualized under the description of discourse strategies comprising clarification requests, confirmation checks, comprehension checks, and repetition (e.g., Long, 1981, 1983; Mackey, 1999; Mackey & Philp, 1998; Oliver, 1998, 2000, 2002; Pica, 1987, 1992; Pica, Holliday, Lewis, & Morgenthaler, 1989, cited in Oliver, 2009 ). As summarized by Oliver (2009) the four strategies can be described as follows: Clarification requests are strategies meant to clarify what the speaker has said. The listener uses those strategies with statements such as “I don’t understand”, wh-questions, yes-no questions and tag questions.
Figure 1. Negotiation process. Source: Sequence adapted from Doughty (2000a, p. 49).
Turn taking is expressed by the learner’s ability to draw the interlocutor’s attention to turn takes in conversation. It is an important aspect of conversation analysis because when turn-taking comes to be associated with break downs, there is a need to signal that something important is happening in the conversation. Negative feedback obtained during negotiation can be facilitative of L2 development , “at least for vocabulary, morphology, and language-specific syntax, and essential for learning certain specifiable L1–L2 contrasts” (Palma,2014, pp.2-3). Long’s (1996) updated version of the interaction hypothesis reveals how negative feedback operates in L2 acquisition. Through negotiation of meaning negative feedback is elicited and directed to draw the learners attention to mismatches between input and output (Stevens, 1999). Long (1996) claims that It is proposed that environmental contributions to acquisition are mediated by selective attention and the learner’s developing L2 processing capacity, and that these resources are brought together most usefully, though not exclusively, during negotiation for meaning. Negative feedback obtained through negotiation work or elsewhere may be facilitative of L2 development, at least for vocabulary, morphology, and language-specific syntax, and essential for learning certain specifiable L1-L2 contrasts (Long 1996:414).
Turn taking can be clearly illustrated when participants allow appropriate opportunities for others to talk, or ‘take the floor’ Tavakoli (2012). In here, the floor is the right to speak and be listened to. Tavakoli (2012) states that “Turn-taking is the set of practices through which conversation is organized and is therefore an important aspect of conversation analysis” p.350.
Turn taking is a basic ingredient in making input comprehensible. Trawinski (2005) claims that in classroom opportunities for turn taking can be created by the learner (self- initiated turns) or by the teacher (teacher- initiated turns). The different aspects of turn taking in language classroom can be illustrated in the following figure:
Figure Turn taking in language classroom ( Allwright, 1991, p. 128 source : Trawinski, 2005, p.65)
Corrective feedback can be provided implicitly or explicitly. Implicit corrective feedback is provided by the listener and involves the form of negotiation strategies such as confirmation checks, clarifications requests, and repetition. These features render corrective feedback and negotiation for meaning closely overlapped (Oliver, 2009 ).The error committed in implicit feedback is not overtly indicated (Ellis, Loewen, and Erlam, 2006). Long’s (1996) revision of his Interaction Hypothesis, with a more highlighting for individual cognitive processing, attention, awareness, focus on form, and negative evidence opened the doors for researchers to focus on different types of corrective feedback (Zoghi, 2016). For example, recasts as can be expressed through short response to correct what seems erroneous (Loewen, 2009), or facilitating the speaker’s self corrections through prompts as another type of feedback (Ammar & Spada, 2006; Lyster, 2004).
It takes the form of recasts, defined by Long (in press) as “a reformulation of all or part of a learner’s immediately preceding utterance in which one or more non-target like (lexical, grammatical etc.) items are replaced by the corresponding target language form(s), and where, throughout the exchange, the focus of the interlocutors is on meaning not language as an object”. (p.2 cited in Ellis, Loewen, and Erlam, 2006).
The effectiveness of corrective feedback is remarkably expressed through the use of DMs in teacher talk which signals politeness and personal stances (Yang, 2014). Explicit corrective feedback is provided by teachers to make learners aware of the form of their linguistic errors or mistakes. However, as Ellis, Loewen, and Erlam (2006) indicate, explicit feedback has two forms: (a) explicit correction, in which the error committed by the learner is clearly highlighted by the teacher, and affords both positive and negative evidence by indicating that what the learner said was incorrect (e.g., “No, not goed—went”) and thus. (b) metalinguistic feedback, unlike explicit correction it affords only negative evidence. For example, “You need past tense,” It is defined by Lyster and Ranta (1997) as “comments, information, or questions related to the well-formedness of the learner’s utterance” (p. 47 cited in Ellis, Loewen, and Erlam, 2006 ). However, as argued by Ellis, Loewen, and Erlam, (2006) “metalinguistic feedback, are more likely to impede the natural flow of communication and to activate the kind of learning mechanisms that result in explicit rather than implicit second language (L2) knowledge” (p. 341).
Besides, corrective feedback jointly with form-focused instruction provided within the context of communicative interaction can promote second language in both the short and long term (White et al 1991; Spada et al 1993).
In relation to feedback received by learners, direct and indirect negative evidence come to inform that a learner’s utterance is ill-formed. Direct negative evidence occurs explicitly to inform the learner that his utterance is incorrect in some way. On the other hand unlike error correction, which is direct negative evidence, indirect negative evidence occurs implicitly in conversational interactions to confirm, query, and restate what the person says. Indirect negative evidence indicates that the learner’s utterance is wrong and does not normally interrupt the flow of communication and is focused on meaning (Tavakoli, 2012).