By Robert William McCaul

Robert William McCaul, winner (with Marek Kiczkowiak) of the TeachingEnglish blog award, examines the influential ideas of linguist Stephen Krashen, and the implications they have for the language classroom.

If you've ever doubted whether you're a good language learner, then bear in mind that you've already learned one language very well indeed – your first. But this raises an interesting question: can adults learn a second language in the same way they learned their first as children? And if so, what are the implications for the classroom?

Stephen Krashen and the acquisition of languages

Perhaps no-one has looked at the question more closely than the linguist Stephen Krashen, who has introduced some of the most influential concepts to the study of second-language acquisition.

In his input hypothesis, first proposed in an article published in 1977, and expanded upon in later years, he makes the distinction between learning: the conscious, traditional grammar-based process in the classroom; and acquisition: essentially how we, as children, pick up our first language. He says that our mistake is trying to teach languages in the same way we teach science, history and mathematics. Instead, he believes that learners should acquire second languages in the same way children learn their first.

Krashen sums up the idea in a famous documentary on the subject called A child's guide to learning languages, produced by BBC Horizon in 1983. In the documentary, he says that acquisition is 'where the action is'. In other words, in every successful example of language-learning – an infant mastering a first language, an adult learner of English scoring a band 9 on the IELTS test – the reason for their success is that they have 'acquired' rather than 'learned' the language.

So, how do children and proficient adult learners perform the seemingly magical trick of mastering a language, and what can teachers learn from this? Krashen offers the following ideas:

1. We acquire languages when we can understand messages

Learners need to be exposed to what Krashen calls 'comprehensible input' – that is, exposure to interesting and understandable listening and reading material. In Krashen's view, we acquire languages when we understand messages. He stipulates that the emphasis should be on meaningful interactions and not on form. When parents speak to their children, for example, the emphasis is on meaning rather than the correct use of grammar. If the child says, 'Daddy fish water!', the parent is likely to respond, 'Yes, you're right, there's a fish in the river', rather than by correcting the child's grammar. The theory here is that exposure to sufficient quantities of comprehensible input always results in acquisition.

2. Getting the right level is crucial

Krashen makes the important point that comprehensible input needs to be at the right level for the learner, namely just higher than the learner's own. He calls this theoretical level 'i + 1'. A good practical example of this in action are graded readers. These are books that are specially created for learners of foreign languages at various levels, such as A2, B1, C2, etc, on the common European framework (CEFR).

3. The silent period

Children don't start speaking their mother tongue straight away. Until they utter their first words, they are acquiring language, even if they are not using it. The miraculous first words and sentences that quickly follow are the result of this acquisition. Adult learners, both inside and outside the classroom, need this silent period, too. Teachers shouldn't be afraid when their students don't participate in debates in class – perhaps they are simply acquiring the language. Moreover, putting pressure on the learner to speak before they are ready will result in anxiety.

4. Anxiety is the student’s arch enemy

This brings me to one of Krashen’s most famous insights, namely the affective filter. This means that the rate of acquisition decreases if we are under stress, or if we experience anxiety. Luckily, most children have a virtually stress-free language-learning environment at home with their mothers and fathers. But for learners of a second language, the classroom can be a cause of anxiety, greatly affecting the way they receive and process comprehensible input.

By contrast, a house party with lots of international guests is a great place to practise languages, as everybody is relaxed and having a good time. Such an environment offers the language learner plenty of comprehensible input, but (hopefully) none of the anxiety. The lesson here for teachers is that they can create a similar environment by turning the classroom into a sort of house party where people feel comfortable and relaxed.

5. The monitor hypothesis

According to Krashen, conscious language-learning cannot be the source of spontaneous speech, it can only monitor output, i.e., production in speech or writing. In other words, when learners freely formulate an utterance in the target language, they can only draw upon their repertoire of acquired language to check whether it is grammatically correct. This reduces errors as the learner can apply consciously learned rules to an utterance before producing it, or after production through self-correction. As many people place a high value on accuracy, especially in formal situations, the existence of the 'monitor' could be seen as a reason for retaining a grammar focus in a given lesson.

One way to apply this in the classroom would be to have learners notice grammatical features in listening and reading texts using a guided discovery approach. For example, if the learners were given a listening task to do on the biography of a famous person who is still alive, the teacher could hand out the transcript and get the students to underline all of the examples of the present perfect tense. This might be followed by a short discussion, led by the teacher, as to why the tense is being used in this particular situation, followed by some concept-checking questions to ensure students understand how to use the target language. However, Krashen is clear that the main focus of classroom activity should be on giving learners as much comprehensible input as possible. Teachers should base their lessons on meaningful interactions with plenty of graded listening and reading input.

6. The natural order hypothesis

The grammar and vocabulary of a language are acquired in the same general order, irrespective of who the learner is, which language they are acquiring and the order of the grammar syllabus. You can teach students reported speech, such as in the sentence, 'she mentioned that she had been at the shop that morning', but learners won’t acquire it unless they are ready to. Certain elements of grammar are 'late-acquired', such as the third person '-s', and others are 'early-acquired'. This explains why my little niece continues to say things like 'Daddy go to work every day', even when she has already mastered more complex grammatical structures such as a conditional sentence like, 'I would do it if I had time'. Evidence for this 'natural sequence' of language acquisition can be found in the morpheme studies by Dulay and Burt. This casts doubt on the teaching of many points of grammar too early, that is, before students are ready to acquire them, such as the future perfect tense at intermediate level.

The advantages children have over adult learners

Before looking at the classroom implications of Krashen’s insights, we should remind ourselves of some of the advantages that children learning their first language have over adults learning a second language. One of the principle advantages is that children are exposed to copious amounts of comprehensible input at just the right level, and there is no pressure on them to speak until they are ready to do so. Children can also take their time and wait until they feel confident before attempting to speak. Moreover, they often have lower expectations of themselves and this helps to ensure that their anxiety levels are low, which, in turn, increases their rate of acquisition.

One of the most surprising things is that when children acquire a language, the language acquisition itself is not their objective. Rather, it is a by-product of the achievement of some other purpose, such as making friends in a school playground. Moreover, they pick up the elements of their first language in its natural order. They are not 'force-fed' grammar too early before their language acquisition devices are ready for it. Instead, they acquire the language first and then consider its structure after acquisition has already taken place. Finally, they learn the elements of a language in the natural order.

The practical implications of Krashen's ideas for the classroom

From Krashen's theories, and having looked at the advantages that children have over adults when it comes to learning languages, we can draw certain conclusions about what conditions make for a successful learning environment. First, class time should be taken up with as much comprehensible input as possible. Second, classes should be stress-free environments where students are encouraged to relax and acquire the language by having fun with it.

One particularly important implication of Krashen’s findings is that students, particularly at lower levels, should have lower demands made on them to speak, and materials and teacher talking time should be modified for each student's level. Furthermore, grammar instruction should be done on a need-to-know basis, and only with older learners. Last, but perhaps most important, lessons should not be based on grammar points, but rather on the exchange of meaning.

Listen to Robert William McCaul and Marek Kiczkowiak discuss Krashen's theories of language acquisition on their award-winning podcast.

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