The Affective Filter Hypothesis

The Input Hypothesis

The Natural Order Hypothesis

The Monitor Hypothesis

The “monitor” is involved in learning, not in acquisition. It is a device for “watchdogging” one’s output, for editing and making alterations or corrections as they are consciously perceived. The Monitor Hypothesis claims that we may call upon learned knowledge to correct ourselves when we communicat e. There must be sufficient time for a learner to choose and apply a learned rule. The language user must be focused on correctness or on the form of the output. The performer must know the rules. According to Krashen, such explicit and intentional learning ought to be largely avoided, as it is presumed to hinder acquisition. Only once fluency is established, should an optimal amount of monitoring, or editing, be employed by the learner.

Krashen has claimed that we acquire language rules in a predictable or “natural” order. Research is said to have shown that certain grammatical structures or morphemes are acquired before others in first language acquisition of English, and a similar natural order is found in second language acquisition.

According to Krashen, comprehensible input (refers to utterances that the learner understands based on the context in which they are used as well as the language in which they are phrased) is “the only cause of second language acquisition”.

The Input Hypothesis claims that an important “condition for language acquisition to occur is that the acquirer understand (via hearing or reading) input language that contains structure “ a bit beyond” his or her current level of competence …. If an acquirer is at stage or level i, the input he or she understands should contain i + 1”. In other words, the language that learners are exposed to should be just far enough beyond their current competence that they can understand most of it but still be challenged to make progress. The input should neither be so far beyond their reach that they are overwhelmed (this might be, say, i + 2), nor so close to their current stage that they are not challenged at all (i + 0).

An important part of the Input Hypothesis is Krashen’s recommendation that speaking not be taught directly or very early in the language classroom. Speech will “emerge” once the acquirer has built up enough comprehensible input (i + 1), after the acquirer has built up linguistic competence by understanding input.

The Affective Filter Hypothesis states that acquirers with a low affective filter seek and receive more input, interact with confidence, and are more receptive to the input they receive. Anxious acquirers have a high affective filter, which prevents acquisition from taking place.

Krashen has claimed that the best acquisition will occur in environments where anxiety is low and defensiveness absent, or, in Krashen’s terms, in contexts where the “affective filter” is low.

These five hypotheses have obvious implications for language teaching. In sum, these are:

1. As much comprehensible input as possible must be presented.

2. Whatever helps comprehension is important. Visual aids are useful, as is exposure to a wide range of vocabulary rather than study of syntactic structure.

3. The focus in the classroom should be on listening and reading; speaking should be allowed to “emerge”.

4. In order to lower the affective filter, student work should center on meaningful communication rather than on form; input should be interesting and so contribute to a relaxed classroom atmosphere.

The Natural approach “is for beginners and is designed to help them become intermediates”. They will understand the speaker of the target language and will be able to convey their requests and ideas. They need not know every word, nor is it necessary that the syntax and vocabulary be flawless. They should be able to make the meaning clear but not necessarily be accurate in all details of grammar.

2. Second Language Acquisition (SLA), as a sub-discipline of applied linguistics, is still a very young field of study. Many researchers agree that the late sixties marked the onset of an intense period of empirical and theoretical interest in how second languages are acquired. The theory of instructed language learning by Roderick Ellis (1994) addresses the role of instruction in L2 acquisition. Ellis has tried to draw together a set of generalisations that might serve as the basis for language teacher education in the form of 'principles'.

Principle 1: Instruction needs to ensure that learners develop both a rich repertoire of formulaic expressions and a rule-based competence

Proficiency in an L2 requires that learners acquire both a rich repertoire of formulaic expressions (which cater to fluency) and a rule-based competence consisting of knowledge of specific grammatical rules (which cater to complexity and accuracy) (Skehan, 1998).

There is now widespread acceptance of the importance played by formulaic expressions in language use. Native speakers have been shown to use a much larger number of formulaic expressions than even advanced L2 learners (Foster, 2001). Formulaic expressions may also serve as a basis for the later development of a rule-based competence

Rule-based competence (i.e. knowledge of specific grammatical rules) through the systematic teaching of pre-selected structures (a focus-on-forms approach, according to Long (1991)) has traditionally been directed at in language instruction. This type of instruction is as likely to result in students learning rote-memorized patterns as in internalizing abstract rules (Myles, 2004).

Thus, clearly, a complete language curriculum needs to ensure that it caters to the development of both formulaic expressions and rule-based knowledge.

Principle 2: Instruction needs to ensure that learners focus predominantly on meaning

It is necessary to distinguish two different senses of the 'focus on meaning'. The first refers to the idea of semantic meaning (i.e. the meanings of lexical items or of specific grammatical structures). The second sense of focus on meaning relates to pragmatic meaning (i.e. the highly contextualized meanings that arise in acts of communication). To provide opportunities for students to attend to and perform pragmatic meaning, a task-based approach to language teaching is required.

It is clearly important that instruction ensures opportunities for learners to focus on both types of meaning but, arguably, it is pragmatic meaning that is crucial to language learning.

In the case of semantic meaning, the teacher and the students can treat language as an object and function as pedagogues and learners. But in the case of pragmatic meaning, they need to view the L2 as a tool for communicating and to function as communicators.

The opportunity to focus on pragmatic meaning is important for a number of reasons:

1. In the eyes of many theorists (e.g. Prabhu 1987; Long 1996), only when learners are engaged in decoding and encoding messages in the context of actual acts of communication are the conditions created for acquisition to take place.

2. To develop true fluency in an L2, learners must have opportunities to create pragmatic meaning (DeKeyser, 1998).

3. Engaging learners in activities where they are focused on creating pragmatic meaning is intrinsically motivating.

To be effective, instruction must include opportunities to create pragmatic meaning, and, ideally, over an entire curriculum, they should be predominant.

Principle 3: Instruction needs to ensure that learners also focus on form

There is now a widespread acceptance that acquisition also requires that learners attend to form. Indeed, according to some theories of L2 acquisition, such attention is necessary for acquisition to take place. Schmidt (1994), for example, has argued that there is no learning without conscious attention to form.

Instruction can cater to a focus on form in a number of ways:

1. Through grammar lessons designed to teach specific grammatical features. An inductive approach to grammar teaching is designed to encourage 'noticing' of pre-selected forms; a deductive approach seeks to establish an awareness of the grammatical rule.

2. Through focused tasks (i.e. tasks that require learners to comprehend and process specific grammatical structures in the input, and/or to produce the structures in the performance of the task).

3. By means of methodological options that induce attention to form in the context of performing a task.

Instruction can seek to provide an intensive focus on pre-selected linguistic forms (as in a focus-on-forms approach or in a lesson built around a focused task) or it can offer incidental and extensive attention to form through corrective feedback in task-based lessons.

There are pros and cons for both intensive and extensive grammar instruction. Some structures may not be mastered without the opportunity for repeated practice. However, intensive instruction is time consuming and thus there will be constraints on how many structures can be addressed. Extensive grammar instruction, on the other hand, affords the opportunity for large numbers of grammatical structures to be addressed. Also, more likely than not, many of the structures will be attended to repeatedly over a period of time. Further, because this kind of instruction involves a response to the errors each learner makes, it is individualized. Arguably, then, instruction needs to be conceived of in terms of both approaches.

Principle 4: Instruction needs to be predominantly directed at developing implicit knowledge of the L2 while not neglecting explicit knowledge

Explicit knowledge 'is the declarative and often anomalous knowledge of the phonological, lexical, grammatical, pragmatic and socio-critical features of an L2 together with the metalanguage for labelling this knowledge' (Ellis, 2004). It is held consciously, is learnable and verbalizable and is typically accessed through controlled processing when learners experience some kind of linguistic difficulty in the use of the L2. Explicit knowledge may assist language development by facilitating the development of implicit knowledge.

Implicit knowledge is procedural, is held unconsciously and can only be verbalized if it is made explicit. It is accessed rapidly and easily and thus is available for use in rapid, fluent communication. In the view of most researchers, competence in an L2 is primarily a matter of implicit knowledge. Implicit knowledge underlies the ability to communicate fluently and confidently in an L2. Thus it is this type of knowledge that should be the ultimate goal of any instructional programme. To develop implicit knowledge learners need the opportunity to participate in communicative activity.

This principle, then, asserts that instruction needs to be directed at developing both implicit and explicit knowledge, giving priority to the former. However, teachers should not assume that explicit knowledge can be converted into implicit knowledge, as the extent to which this is possible remains controversial.

Principle 5: Instruction needs to take into account the learner's 'built-in syllabus'

Early research into naturalistic L2 acquisition showed that learners follow a 'natural' order and sequence of acquisition (i.e. they master different grammatical structures in a relatively fixed and universal order and they pass through a sequence of stages of acquisition on route to mastering each grammatical structure). This led researchers like Corder (1967) to suggest that learners had their own 'built-in syllabus' for learning grammar as implicit knowledge. Krashen (1981) famously argued that grammar instruction played no role in the development of implicit knowledge (what he called 'acquisition'). Grammar instruction could contribute only to explicit knowledge ('learning').

A number of empirical studies designed to (1) compare the order of acquisition of instructed and naturalistic learners (e.g. Pica, 1983), (2) compare the success of instructed and naturalistic learners (Long, 1983) and (3) examine whether attempts to teach specific grammatical structures resulted in their acquisition (Ellis, 1984) showed that, by and large, the order and sequence of acquisition was the same for instructed and naturalistic learners; that instructed learners generally achieved higher levels of grammatical competence than naturalistic learners and that instruction was no guarantee that learners would acquire what they had been taught. This led to the conclusion that it was beneficial to teach grammar, but that it was necessary to ensure it was taught in a way that was compatible with the natural processes of acquisition.

How, then, can instruction take account of the learner's built-in syllabus? There are a number of possibilities:

1. Adopt a zero grammar approach, as proposed by Krashen. That is, employ a task-based approach that makes no attempt to predetermine the linguistic content of a lesson.

2. Ensure that learners are developmentally ready to acquire a specific target feature.

3. Focus the instruction on explicit rather than implicit knowledge

Principle 6: Successful instructed language learning requires extensive L2 input

Language learning, whether it occurs in a naturalistic or an instructed context, is a slow and laborious process. Children acquiring their L1 take between two and five years to achieve full grammatical competence, during which time they are exposed to massive amounts of input. Ellis and Wells (1980) demonstrated that a substantial portion of the variance in speed of acquisition of children can be accounted for by the amount and the quality of input they receive. The same is undoubtedly true of L2 acquisition.

If learners do not receive exposure to the target language they cannot acquire it. In general, the more exposure they receive, the more and the faster they will learn. How can teachers ensure their students have access to extensive input? In a 'second' language teaching context, learners can be expected to gain access to plentiful input outside the classroom. In a 'foreign' language teaching context (as when French or Japanese is taught in schools in the United Kingdom or United States), there are far fewer opportunities for extensive input. To ensure adequate access, teachers need to:

1. Maximise use of the L2 inside the classroom. Ideally, this means that the L2 needs to become the medium as well as the object of instruction.

2. Create opportunities for students to receive input outside the classroom. This can be achieved most easily be providing extensive reading programmes based on carefully selected graded readers, suited to the level of the students. Also, ideally, if more resources are available, schools need to establish self-access centres which students can use outside class time. Successful FL learners seek out opportunities to experience the language outside class time. Many students are unlikely to make the effort unless teachers (a) make resources available and (b) provide learner-training in how to make effective use of the resources.

It can be claimed with confidence that, if the only input students receive is in the context of a limited number of weekly lessons based on some course book, they are unlikely to achieve high levels of L2 proficiency.

Principle 7: Successful instructed language learning also requires opportunities for output

Contrary to Krashen's insistence that acquisition is dependent entirely on comprehensible input, most researchers now acknowledge that learner output also plays a part. Skehan (1998) drawing on Swain (1995) summarises the contributions that output can make:

1. it serves to generate better input (through the feedback that learners' efforts at production elicit);

2. it forces syntactic processing (i.e. obliges learners to pay attention to grammar);

3. it allows learners to test out hypotheses about the target language grammar;

4. it helps to automatize existing knowledge;

5. it provides opportunities for learners to develop discourse skills (e.g. by producing 'long turns');

6. it is important for helping learners to develop a 'personal voice' (by steering conversation on to topics they are interested in contributing to).

Ellis (2003) adds one other contribution of output:

7. it provides the learner with 'auto-input' (i.e. learners can attend to the 'input' provided by their own productions).

The importance of creating opportunities for output constitutes one of the main reasons for incorporating tasks into a language programme. Controlled practice exercises typically result in output that is limited in terms of length and complexity. They do not afford students opportunities for the kind of sustained output that theorists argue is necessary for interlanguage development. Research (e.g. Allen et al, 1990) has shown that extended talk of a clause or more in a classroom context is more likely to occur when students initiate interactions in the classroom and when they have to find their own words. This is best achieved by asking learners to perform oral and written tasks.

Principle 8: The opportunity to interact in the L2 is central to developing L2 proficiency

Input and output both co-occur in oral interaction. As Hatch (1978b) famously put it 'one learns how to do conversation, one learns how to interact verbally, and out of the interaction syntactic structures are developed'. Thus, interaction is not just a means of automatizing existing linguistic resources but also of creating new resources. According to the Interaction Hypothesis (Long, 1996), interaction fosters acquisition when a communication problem arises and learners are engaged in negotiating for meaning. The interactional modifications arising help to make input comprehensible, provide corrective feedback, and push learners to modify their own output in uptake.

What then are the characteristics of interaction that are deemed important for acquisition? In general terms, opportunities for negotiating meaning and plenty of scaffolding are needed. Johnson (1995) identifies four key requirements for interaction to create an acquisition-rich classroom:

1. Creating contexts of language use where students have a reason to attend to language

2. Providing opportunities for learners to use the language to express their own personal meanings

3. Helping students to participate in language-related activities that are beyond their current level of proficiency

4. Offering a full range of contexts that cater for a 'full performance' in the language.

Thus creating the right kind of interaction for acquisition constitutes a major challenge for teachers. One solution is to incorporate small group work into a lesson. When students interact amongst themselves, acquisition-rich discourse is more likely to ensue. However, there are a number of dangers in group work which may militate against this (e.g. excessive use of the L1 in monolingual groups).

Principle 9: Instruction needs to take account of individual differences in learners

There is considerable variability in the rate of learning and in the ultimate level of achievement. In particular, learning will be more successful when:

1. The instruction is matched to students' particular aptitude for learning.

2. The students are motivated.

Teachers can cater to variation in the nature of their students' aptitude by adopting a flexible teaching approach involving a variety of learning activities; using simple learner-training materials designed to make students more aware of their own approaches to learning and to develop awareness of alternative approaches. Thus, increasing the range of learning strategies at learners' disposal is one way in which teachers can help them to learn. Such strategy training needs to foster an understanding that language learning requires both an experiential and an analytical approach and to demonstrate the kinds of strategies related to both approaches.

Dornyei's research has shown the kinds of teaching strategies that teachers can employ to develop and maintain their students' intrinsic motivation. Dornyei (2001) also makes the obvious point that 'the best motivational intervention is simply to improve the quality of our teaching' (p. 26). He points in particular to the need for 'instructional clarity' (such obvious recipes as 'explain things simply' and 'teach at a pace that is not too fast and not too slow'). Teachers also need to accept that it is their responsibility to ensure that their students are motivated and stay motivated and not bewail the fact that students do not bring any motivation to learn the L2 to the classroom. While it is probably true that teachers can do little to influence students' extrinsic motivation, there is a lot they can do to enhance their intrinsic motivation.

Principle 10: In assessing learners' L2 proficiency, it is important to examine free as well as controlled production

Norris and Ortega's (2000) meta-analysis of studies investigating form-focussed instruction demonstrated that the extent of the effectiveness of instruction is contingent on the way in which it is measured. They distinguished four types of measurement:

1. metalinguistic judgement (e.g. a grammaticality judgment test)

2. selected response (e.g. multiple choice)

3. constrained constructed response (e.g. gap filling exercises)

4. free constructed response (e.g. a communicative task).

They found that the magnitude of effect was greatest in the case of (2) and (3) and least in (4). Yet, arguably, it is (4) that constitutes the best measure of learners' L2 proficiency, as it is this that corresponds most closely to the kind of language use found outside the classroom. The ability to get a multiple choice question right amounts to very little if the student is unable to use the target feature in actual communication.

Free constructed responses are best elicited by means of tasks. The performance elicited by means of tasks can be assessed in three ways (Ellis, 2003); (1) a direct assessment of task outcomes, (2) discourse analytic measures and (3) external ratings. (2) is not practical for busy classroom teachers as it requires transcribing speech and then painstakingly calculating such measures as number of error free clauses and clause complexity. (3) is practical but it requires considerable expertise to ensure that the ratings of learner performance are valid and reliable. (1) holds out the most promise. However, it is only possible with closed tasks (an i.e. task for which there is a single correct outcome). An example would be a 'Spot the Difference Task' where learners are asked to interact in order to find a specified number of differences in two similar pictures. In this task, assessment would consist of establishing whether they were able to successfully identify the differences.

These general principles have been derived from Ellis's understanding of SLA. This model has its limitations and is open to criticism, in particular that it is not socially sensitive because it fails to acknowledge the importance of social context and social relations in the language learning process

Дата добавления: 2014-01-11