Second language acquisition. External linguistic factors and the role of input

Essay, 2017

11 Pages, Grade: 20 out of 20


The Role and Implications of Input in Second Language Acquisition

Mohammad Javad Moafi


Over the last few decades, researchers have directed their attention to the external linguistic factors that offer assistance to second language learners in acquiring a target language. External factors relate to the environment in which learning takes place. This involves considering the role played by the social situation in which learning takes place and the language the learner is exposed to input (Ellis, 1994). The role of input is undoubtedly crucial in the process of second language learning. Mackey (2012) defines input as "the language that is available to a learner through any medium. In all approaches to SLA, input is recognized as an essential basic component in the learning process" (p. 9).

According to Mackey (2012), it is universally accepted that in order to acquire an L2, learners need to be exposed to the target language. As Gass (1997) mentions, the concept of input is perhaps the single most important concept of second language acquisition, and no individual can learn a second language without some sort of input. The importance of the input has been advocated by a variety of learning theories. According to Ellis (1994), theories of SLA attach different importance to the role of input in language acquisition process but they all acknowledge the need for language input. In many approaches to SLA, input is considered as being a highly essential factor while in other approaches it has been neglected to a secondary role.

Keywords: output, input, interaction

Input and Language Learning Theories

In this relation, Ellis (1994) considered the role of language input in SLA based on behaviorist, mentalist, and interactionist theories of language learning. The behaviorists consider a direct relationship between input and output. For the behaviorists, language acquisition is controlled by external factors among which language input which consists of stimuli and feedback is central. The mentalist theories also claim that input is needed for SLA but it is merely considered as a trigger that activates the internal mechanism. The interactionist theories of SLA highlight the importance of both input and internal language learning processing. They view language acquisition as the outcome of an interaction at the discourse level between the learners’ mental abilities and the linguistic environment and input. This theory is more social in orientation, and verbal interaction is of crucial importance for language learning (Ellis, 1994).

Input and SLA Models

In order to understand the role of input, it is first necessary to examine the relationship between input and second language acquisition. According to Nizegorodcew (2007), there are different SLA models which consider L2 input as one of the crucial factors in language acquisition. They include: Input, Interaction, and Output Models

Input Model

The first model which treated input as the main factor in L2 acquisition is Krashen’s (1981) Comprehensible Input Hypothesis. Krashen (1981) claims that the first necessary condition for the input to be acquired is its comprehensibility, which is gained by its approximate level of difficulty, slightly higher than the learner’s present proficiency level. Such input is called roughly tuned input.

However, based on McLaughlin (1987), critics of Krashen’s Comprehensible Input Hypothesis believes that his concepts are vague; it is not clear what a slightly higher level of difficulty is, and it is not explicitly stated whether they apply to all aspects and levels of L2 acquisition. Moreover, Krashen’s theory equates L2 acquisition and L2 comprehension, by claiming that once L2 input has been comprehended, it has also been automatically acquired, which, obviously, is not the case.

Interaction Model

A similar SLA model, equating comprehension with acquisition of L2 input data was proposed by Long (1981) as the Interaction Hypothesis. Long (1985) claims that the input provided by native speakers for non-native speakers must be adjusted in interaction to become comprehensible. He identifies a few types of interactional adjustments in conversations between native and non-native speakers, such as confirmation checks, clarification requests and comprehension checks. Long (1985) concludes that there exists an indirect causal relationship between linguistic and conversational adjustments and SLA.

In a weak version of the Interaction Hypothesis, it is claimed that the feedback on errors, received from the native speaker interlocutor during interaction can facilitate L2 development, but probably only in some aspects of L2 learning (Long, 1996).

Output Model

Swain (1985) in a modification of the Comprehensible Input Hypothesis argues that comprehensible input alone, even in large quantities, cannot make L2 learners fully competent target language speakers. Based on data collected from a Canadian French immersion program, Swain (1985) proposed the Comprehensible Output Hypothesis. The Output Hypothesis suggests that, in addition to input, learners need opportunities to produce and use language (i.e. to create output) in order to advance their L2 development.

Input and SLA Research

Regarding the role of input in SLA, there are two major lines of research: quantity of input, and quality of input.

Quantity of Input

In the first major line of inquiry, researchers have investigated the relationship between the quantity of input to learners and various measures of second language proficiency. Studies concerned in particular with the quantity of input, based on Seliger (1977), have provided evidence for the hypothesis that learners who have the opportunity to receive the most target language input are those who gain greater proficiency. For example, Seliger (1977) found that L2 learners who were exposed to significantly more input from sources in and outside of the classroom environment were more proficient than students who did not have the opportunity to be exposed more to TL input. However, due to the fact that the process of language acquisition and learning is under the influence of many co-occurring variables (such as learner variables, opportunities for interaction with NSs, conditions under which learning takes place, etc.), it is possible that the above mentioned evidence may be due to the quality of input the L2 learners have received as much as to the greater quantity of exposure to the target language. Thus, it may be the case that not only the quantity, but also the quality of input is important to L2 learning outcomes.

Quality of Input

The second major line of inquiry for research studies has focused on the quality of input to second language learners. There are a number of ways to evaluate the quality of input. In some studies, input quality is manipulated as the frequency and order of presentation of particular linguistic structures in the input to learners (Long, 1981). On the basis of these studies, there is evidence that frequency of exposure to structures in the linguistic input may relate to more accurate production of these structures in required communicative contexts.

In other studies, the focus has been on other qualitative aspects of input to L2 learners, in particular modifications made by teachers to increase learners’ ability to comprehend their speech, what Krashen (1981) termed comprehensible input. Krashen (1981) hypothesizes that in order for input to become intake and, therefore, to support language acquisition, it must first be comprehensible to the learner, and this may be achievable if speech adjustments are made when providing input to nonnative speakers.

Potential Sources of Comprehensible Input

Based on xiaohui (2010), Given the significance of input comprehension in language acquisition, current SLA research has tried to identify what makes input comprehensible to the learner, and what contributions comprehensible input makes to language acquisition. In this regard, Park (2002) identifies three linguistic environments as the potential sources of comprehensible input for L2 acquisition: pre-modified input, interactionally modified input, and modified output.

Pre-modified input

This potential source of input is based on the Krashen's input hypothesis (1981). According to Park (2002), the input is modified or simplified in some ways before the learners see or hear it. There are two kinds of premodified input: simplification and elaboration. Simplified input can be in the form of less complex syntax and limited vocabulary. In simplified input, in order to make the original input comprehensible for the learners, all potential unfamiliar and unknown words are omitted from the text. Input elaboration, however, retains difficult vocabulary items and complex syntactic structures beyond readers’ acquired language proficiency. It attempts to increase text comprehensibility by way of providing definitions of difficult vocabulary items, paraphrasing sentences containing complex syntactic structures, and enriching semantic details (Park, 2002). In reviewing 12 empirical studies on input simplification and elaboration, Parker and Chaudron (1987) cited in Park (2002) report that linguistic simplification in the form of simplified syntax and vocabulary failed to have a significantly positive effect on comprehension, whereas an elaborative modification was found to enhance comprehension. Hence, they suggest that one should modify input in the direction of elaboration rather than syntactic simplification. Kim (2003) cited in xiaohui (2010), also states that input modification in the direction of elaboration is preferred in SLA on the grounds that elaborated input retains the material that L2 learners need for developing their interlanguage and provides them with natural discourse model. It has been noted that elaborated adjustments have the advantage of supplying learners with access to the linguistic items they have not yet acquired (Larsen-Freeman & Long, 1991).

However, there have also been reports of evidence that different types of modifications may have differential effects for learners at different proficiency levels. According to Oh (2001), modified input (whether simplified or elaborated) enhances NNS comprehension. However, not all types of modified input have proved to be equally effective. Oh (2001) speculates that input simplification may facilitate comprehension for beginners, and elaborative modifications may be more suitable for advanced students.

Intearactionally Modified Input

The second potential source of comprehensible input for L2 learning is interactionally modified input. Long (1981) characterizes interactionally modified input as native speaker- non native speaker interactions in which both of them have to modify and reconstruct the interaction in order to arrive at a mutual understanding. This interaction has special features which help the participants negotiate meaning. Long (1981) has asserted that NNSs and NSs employ some strategies in their social discourses, including some aspects of conversations such as comprehension checks, clarification requests, and self and other repetitions and expansions. The speakers modify interactions using these strategies in order to avoid or solve conversation problems and repair discourse when misunderstanding sequences arise. When L2 learners face communicative problems and they have the opportunity to negotiate on solutions to them, they are able to learn language (Long, 1981).


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Second language acquisition. External linguistic factors and the role of input
Islamic Azad University
20 out of 20
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ISBN (eBook)
external, second
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Dr. Mohammad Javad Moafi (Author), 2017, Second language acquisition. External linguistic factors and the role of input, Munich, GRIN Verlag,


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