Interlanguage, multi-competence and the problem of the ‘second’ language

Vivian Cook 
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Vivian Cook, University of Newcastle upon Tyne, April 2006

NB Figures gone berserk Draft of paper in Rivista di Psicolinguistica Applicata

Ferdinand de Saussure remarked almost a hundred years ago, 'Other sciences work with objects that are given in advance and that can then be considered from different viewpoints; but not linguistics' (de Saussure, 1916; trans. 1959, p. 8). So what is the object of second language acquisition research? While seldom discussed, finding an answer to this question determines the nature of the whole field, its research questions, its conclusions and its applications. This paper attempts to explore what second language acquisition research is about from the multi-competence perspective.

1. Interlanguage and multi-competence

One of the principles that put SLA research on its feet as an independent discipline was the independent grammars assumption that learners’ language was independent of the target language, called by Selinker (1972) ‘interlanguage’. The second language (L2) learner’s variety of language is created out of five basic processes: language transfer, overgeneralisation of L2 rules, transfer of training, overgeneralisation of L2 rules, strategies of L2 learning, and communication strategies (Selinker, 1972); it does not depend upon the second language alone. In principle the interlanguage formulation gave SLA research the chance of specifying an object for L2 learning; the learner knew a language that was not the L2 but was nevertheless a language, an entity of its own. This is shown in Figure 1.


                   first                                 independent                              second

                language                                language                              language

                    (L1)                            (interlanguage)                          (L2)


Figure 1.  The learner's independent language system (interlanguage)

The concept of interlanguage led primarily to SLA research dealing with the strategies and processes of learning and use, i.e. the content of the processes box, rather than to descriptions of interlanguage competence. Though interest in the classic idea of transfer has waned, strategies approaches to L2 learning and communication became major industries in the 1980s.

The justification for interlanguage as an independent system had to wait for the European Science Foundation project’s discovery that learners of five different L2s with six different L1s all arrived at the same basic grammar, regardless of the first or second language involved (Klein & Perdue, 1997). The learners’ grammar had three rules; a sentence may consist of a Noun Phrase, Verb and optional second Noun phrase, lui travaille or il travaille déjeuner, or of a Noun Phrase, a copula and an Noun Phrase Adjective or Prepositional Phrase it's un pitou, or of a Verb and a Noun Phrase monter ça (examples from a young English/French bilingual child (Genesee transcripts in CHILDES)). And that’s it. The rules are created by the learner despite the grammars of the target language and the first language. Interlanguage was then a reality: L2 learners did create a grammar of their own out of multiple sources, just as children do when learning a first language.

2. Interlanguage and the second language

Some of the problems of this conceptualisation are inherent in Figure 1. The first language on the left-hand side of Figure 1 describes how the individual knows and uses the first language; the interlanguage in the centre describes how the learner knows and uses the second language.

But the second language on the right-hand side refers to what someone else knows. It no longer concerns the knowledge inside one person’s head but that inside two people’s heads. The relationship between the L1 and the interlanguage is internal to the mind of the learner; the relationship between the interlanguage and the L2 is external and relates to another mind. The L2 is only a second language from the perspective of the L2 learner; to its possessor it is an L1. Hence we can call it L1 (Other Language) with the bracketed label reminding us that it is an other language from the L1 in the L2 learner’s mind. This is shown in Figure 2.

                          L2 learner                              Speaker of the other language

Figure 2. Interlanguage seen as the possession of individuals

In other words ‘second language’ has no meaning in terms of the psychological model of the L2 learner: for the monolingual native speaker it is their first language; for the L2 learner it is their interlanguage. When we talk of the L2 learner acquiring a second language, we ‘really’ mean an interlanguage; when we speak of the second language they are acquiring we mean someone else’s first language. Nevertheless it is perhaps unwise to abandon the use of the term ‘second language’ altogether and it will be used for the rest of this paper, subject to all these strictures.

3. The ‘language’ in second language acquisition

Chomsky has often pointed out that the word ‘language’ is ambiguous. It may refer to the internal (I) language that is a psychological state of knowledge in the mind of the individual; the term “language” is used … to refer to an internal component of the mind/brain’ (Hauser, Chomsky & Fitch, 2002, p. 1570); grammar is the person’s knowledge of language. Or it may refer to an External (E) language set of sentences that have actually occurred ‘understood independently of the properties of the mind’ (Chomsky, 1986, p. 20); from an I-language perspective language is a derived notion – an epiphenomenon: ‘The grammar in a person’s mind/brain is real ... The language (whatever that may be) is not’ (Chomsky, 1982, p. 5).

As well as these two technical senses there is also the ‘common-sense’ use of ‘language’ to refer to the social construct spoken by a group of people – the French language, the Chinese language and so forth– in other words an institutionalised abstraction of shared knowledge. This shades into the use of “language” to refer to a socio-political concept; Chinese is a language despite having at least eight mutually incomprehensible spoken forms called ‘dialects’; Danish and Swedish are different languages despite being mutually comprehensible.

To sum up, a language is either I-language knowledge in a single mind (often referred to simply as a grammar) or an E-language corpus of sentences that have been uttered or an sociological abstraction about shared behaviour of some community.  The first language and the interlanguage in Figure 2 are then clearly I-language, as is the ‘Other language’ (i.e. another person’s L1). The interlanguage was also treated by Selinker in the corpus sense as ‘the utterances which are produced when the learner attempts to say sentences of a TL [target language]’ (Selinker, 1972). In the sociological sense an interlanguage lacks any community of mutually intelligible speakers, except more or less by accident where a group of students in the same environment have similar interlanguages.

One alternative is to relate interlanguage to some existing language. Weinreich (1953, p. 7) said that ‘A structuralist theory of communication which distinguishes between speech and language ... necessarily assumes that “every speech event belongs to a definite language”’. In this view whatever somebody says belongs either to language A or to language B. So what language does the L2 learner’s interlanguage belong to in this broad sense? In practice interlanguages have been spoken of as an English interlanguage, a French interlanguage, etc, as if they belong to a family of English-like languages, French-like languages, etc. But the independent grammars assumption refuses to class the learner’s utterances as either A or B but as a third language C; even if the learners are on their way to B, their interlanguage utterances do not belong to B by definition since they have systems of their own, as the ESF work shows so clearly.

What of the term ‘second language’? It could be used in an E-language sense to mean the sentences the learner has actually encountered, i.e. all the evidence from which the learner constructs the interlanguage, what SLA researchers normally called the input. This input language would have many unique properties of its own, varying according to the learner’s situation as student or immigrant, say; to establish a second language in this sense would be to do a proper description of the grammar in all the sentences the learner hears. Nor is the L2 learner encountering English or French in the common-sense meaning since that is an abstraction for a community of speakers. The second language does not come into Figure 2, except in so far as it refers to an E-language set of sentences. Most earlier research in SLA research interpreted L2 both as the knowledge of the Other Language in the mind of the monolingual native speaker – whatever the native speaker does is right – and in the commonsense meaning of communal property. As we shall see this denies the independence of the interlanguage by making it approximate to something it could never actually be, the first language in the mind of the monolingual.

4. multi-competence and the language integration continuum

To return to Figure 2, the L1 and the interlanguage are in the mind of the same person; the ‘Other language’ is in the mind of another. But there was no term that referred to the whole knowledge of language in the L2 learner’s mind; so Cook (1990) coined the term ‘multi-competence’  defined as ‘the knowledge of one or more languages in the same mind’.  This might then be an L1 and an interlanguage, two L1s as in the case of early childhood bilinguals, or more complex possibilities.

Subsequently it became clear that the term ‘L2 learner’ was too restricted; people who acquire their first language are not regarded as learners throughout their lives but are supposed to have reached some sort of equilibrium. Why should people acquiring a second language be treated differently when many of them may also be in a stable L2 state? Hence the term ‘L2 user’ was introduced to reflect this status. Rather than being Tolstoy’s perpetual student in The Seagull, L2 users are using the language. The term ‘L2 user’ is used for people who know and use a second lang­uage at any level; multi-competence is not restricted to the high-level of balanced bilinguals but concerns the mind of any L2 user at any level of achievement

Now that the task of SLA research was seen as looking at one mind with more than one language, attention started to focus on new research questions, in particular on the relationship between two languages in the same mind. With the L2 of Figure 1 out of the picture, a number of new relationships between the two components of L1 and interlanguage could be investigated. The logical possibilities were:

These three alternatives do not represent either-or choices but points on an integration continuum with two idealised endpoints (Francis, 1999); in between  complete separation for the two languages at one end and complete integration at the other come a variety of possible relationships, shown in Figure 3.

        Separation                      interconnection                       integration

Figure 3. The integration/separation continuum of possible relationships in multi-competence (adapted from Cook, 2002)

This continuum captures a number of alternative relationships. It is not intended to have a direction from left to right or vice versa, even if a left-to-right development is true for some L2 learners Some people may start with complete separation and progress to complete integration. Some young children may start from complete integration - the child studied by Genesee mentioned earlier produced sentences such as what c'est ça? and I trouve it - and progress to separation; for example Taeschner (1983) found an initial stage at which bilingual children acquiring Italian and German had a single lexical system, which separated at the next stage into two lexicons with one syntax. Some people may stay at the separation end despite high levels of competence, e.g. being unable to translate between their languages. The point upon the continuum may vary according to the aspect of language involved either across learners or within the mind of the same person; vocabulary may be highly integrated, syntax separated. Paradis and Genesee (1996) for example showed that L2 children developed the syntactic properties of English and French separately. The relationship may depend upon the idiosyncratic elements in the L1 and in the L2; for example L2 users with similar L1 writing systems to the second lang­uage can, within limits, make use of their L1 system; L2 users with completely different L1s need to acquire a new system: Chinese students with a meaning-based L1 writing system read English at a speed of 88 words per minute, compared to 110 for Spanish students with a sound-based L1 writing system (Haynes & Carr, 1990).

5. Who speaks the second language?

Let us deconstruct a bit more the language situations involved in second language acquisition. This does not consist of two monolithic languages in the social sense, say the English language and the Italian language but involves a variety of types of speaker and situation.

- types of native speaker

Clearly the concept of the native speaker involves considerable idealisation from the actual people in the world. If you are a native speaker of French, say, does this means you speak like people in Paris, people in Brittany, in Lausanne, in Brussels, in Quebec City, in Jersey, in Brazzaville or in Louisiana? Like old people or like young people? Like upper class people or lower class people? All of these have different accents and partly different vocabularies and grammars. Standard French for example has the double negative ne pas but ne is ‘dropped’ by younger people 81% of the time, by women 57% of the time and by the lower class 84% of the time (Ashby, 1981). My use of nonante rather than quatre-vingt-dix for 90 shows early exposure to Swiss French, frowned on by French teachers in England. There are many varieties of French or indeed of any ex-colonial language like Spanish, Portuguese or English, each of them with their own sphere of existence. Imposing a hierarchy of respectability upon them is simply a matter of language power. The social construct of the whole language as a whole disguises the sheer variation between its speakers.

- varieties of multilingual community

A related problem is the mixture of languages within one country’s borders. Italy has 33 languages for instance; out of a population of 55 million, 8.8 speak Lombard, 7 Neapolitan, 4.8 Sicilian, 3.1 Piemontese, 2.2 Venetian, 2.0 Emiliano-Romagnolo, 1.9 Ligurian, 0.8 Friulian and 3.5 million deaf people may speak Italian Sign Language (figures from Ethnologue (Gordon, 2005)). While there are disputes about the differences between languages and dialects and so on, this multilingualism clearly has all sorts of repercussions for SLA research about the rarity of the monolingual native speakers of standard forms of the language.

L2 users come from these multilingual situations. Schmid (2005) describes Italian children in German-speaking areas of Switzerland whose parents speak an Italian dialect but encourage their children to speak standard Italian; outside their homes they encounter Swiss German except in school where High German is used; their minds contain two languages and two dialects of each, creating problems when they learn to read in what is effectively their fourth system, i.e. High German. Randall (2005) looked at Singapore which has four official languages, Mandarin, Bahasa Malaysia, Tamil and English Chinese, any of which may be spoken by children acquiring English, as well as Cantonese, and Hokkien. Even in England a survey of London found that 32% of children spoke languages other than English at home and that 300 different languages were spoken (Baker & Eversley, 2000). L2 users living in multilingual communities are then having to fit into diverse situations of language use; the idealised picture of the student sitting in a classroom studying the language of people who live a thousand miles away is true of only a few situations today.

 - heritage languages

In many countries there are pools of speakers of non-indigenous languages in communities that may well have been there for generations, German in Pennsylvania, Polish in West London. Increasingly these are called ‘heritage’ languages. The varieties that they speak may well be different from the language as spoken in their original countries for two reasons:

Many L2 learners come from such communities. The language they are acquiring is no longer the same as the ‘standard’ but may differ in various ways. Comparisons of interlanguage with a standard form of a language in the social sense may then be misleading as their ‘deviations’ may simply show they are acquiring the language variety around them not that spoken elsewhere.

- international languages

Some languages escape from the hands of their native speakers to be used by non-native speakers with fellow non-native speakers. This is the case for an artificial language like Esperanto, spoken by nobody as a first language; its popularity has, however, nowadays been overtaken by Klingon and one baby has allegedly been raised bilingually in English and Klingon ( It is also the case with pidgins devised for communication between groups speaking different languages; Schmid (1994) found an Italian pidgin developing in Spanish-speaking workers in German-speaking Switzerland; such pidgins may become creoles like Louisiana French and the Portuguese-based Papiamento when children learn them as native speakers. An interesting case has been the development of a new sign language in Nicaragua, the first group of children speaking it as a pidgin, the next group as native speakers (Senghas, Kita & Asli Özyürek, 2004).

This shades over into languages that are used as lingua francas almost regardless of whether they have native speakers or not. Latin for instance was used by the educated and the clergy across Europe for many years long after the Romans had ceased to exist. In Africa 770 thousand people speak Swahili as an L1, 30 million as a lingua franca with speakers of different L1s.

Often the language of the former colonial power is adopted by the ex-colony as an official language, whether French in Burkina Fassa, English in Botswana, Portuguese in Angola, Spanish in Paraguay, Dutch in Suriname or Danish in Greenland. Not only does this create local varieties of the language, such as Singlish in Singapore, but also large numbers of people learning English as an international language to talk to the rest of the world. A distinctive variety of English as Lingua Franca (ELF) may then be emerging (Seidlhofer, 2004), divorced from the native speaker of English and having its own community of L2 speakers, as Latin once did, and indeed still does in some organisations of the Roman Catholic Church.

6. The nature of the L2 user

To recapitulate, the interlanguage hypothesis insisted that L2 users had independent language systems in their own right. SLA research often claimed to be in the interlanguage tradition yet it saw its learners as failures for not speaking like natives. To take some representative quotations:

‘Very few L2 learners appear to be fully successful in the way that native speakers are’ (Towell & Hawkins, 1994, p. 14)


‘Relative to native speaker’s linguistic competence, learners’ interlanguage is deficient by definition’ (Kasper & Kellerman, 1997, 5).

Anything that regards the L2 user as a pale imitation of the native speaker is in breach of the interlanguage assumption: since L2 users cannot be native speakers by definition, it is prejudicial to measure them by the standards of a group to which they can never belong, as it would be wrong to judge men’s language against women’s. As Sridhar and Sridhar (1986) pointed out some time ago:

 ‘Paradoxical as it may seem, Second Language Acquisition researchers seem to have neglected the fact that the goal of SLA is bilingual­ism’.

This can then be called the monolingual fallacy. The view of entire separation between languages is a monolingual view of bilingualism as it treats both languages as if they were the first language, denying the reality of bilingualism (Grosjean, 1989). Even bilinguals, according to Grosjean, 'often assume and amplify the monolingual view and hence criticise their own language competence'.

Within the multi-competence perspective, much work has tried to study just what makes the L2 user different from a monolingual native speaker apart from their extra ability to use another language. Let us take three aspects of this:

- the L2 user’s second language

It hardly needs documenting that the language of second language users differs from that of monolingual native speakers. Accent is still different even when say written skills exceed the average native, as is the case with writers such as Joseph Conrad writing in English as his third language.

A note of warning has, however, to be sounded in that the ability to pass as native may be far more widespread than people have credited if it is made specific to certain skills and situations (Piller, 2002). Successful passing is invisible, as the financier Robert Maxwell (of Czech origin) and the film star Laurence Harvey (of Yiddish/Lithuanian background) show. Alan Turing claimed that the test of Artificial Intelligence was passing for a human being (Turing, 1950); the Loebner Prize of $100,000 for achieving this is competed for each year but has never been won in full. John Searle’s alternative of the Chinese Room was almost bilingual in that the problem was to know if the person locked in the room knew Chinese or not from output produced by rote means from input in characters (Searle, 1980). Similarly an L2 test of passing should be how long and in what circumstances the speaker can pass, not an absolute overall test.

The problem is when this difference counts as failure. It is not just the SLA researchers who see these differences from the monolingual native speaker as constituting a problem, but also many L2 users, who lament that their language is not like that of a monolingual native speaker after many years of application. People frequently come up to me at conferences after I have given a talk on multi-competence to point out angrily that, as a monolingual English speaker, I cannot speak for bilingual’s aspirations, which are to pass for natives. Well this reinforces Grosjean’s claim that bilinguals themselves have been forced into the monolingual fallacy.

The argument has usually been conducted in terms of the advanced L2 user, what came to be called ‘ultimate attainment’ in SLA research. The original work that stimulated discussion in this area was a study by Coppieters (1987) who gave grammaticality judgements to near-native and native speakers of French on nine syntactic structures. None of the 21 L2 users fell within the bounds of the native group.  In terms of qualitative results, the chief problems were with semantic interpretation of such features as the distinctions between the imparfait and the passé composé and between ce and il. The ulti­mate attainment of the L2 users differed from that of the native speakers. In later research Birdsong (1992) showed that this effect only occurred when the subjects were averaged into a group; when treated as individuals. 15 of the 20 near-natives were within the native speaker range. White & Genesee (1996) continued this approach by comparing native speakers of English and L2 learners, concluding that ‘Ultimate attainment in an L2 can indeed be native-like in the UG domain’ (White & Genesee, 1996, 258). In terms of accent Neufeld (1977) managed to teach L1 English students to pass for native Japanese in eighteen hours; Bongaerts and his colleagues have been describing a group of Dutch speakers who can pass for natives (Bongaerts, Planken & Schils, 1995; Bongaerts, van Summeren, Planken & Schils, 1995).

The consensus seems to be that some L2 users are indistinguishable from monolingual native speakers. So what? This is simply a denial of the right of the L2 user to be themselves rather than imitation native speakers. Sure some L2 users may pass an L2 Turing Test; some Worcester Pearmain apples are pear-shaped. Our focus should be on the majority of L2 users who do not pass the Turing Test. Another side to this is the perennial debate about the availability of Universal Grammar in second language acquisition; research is presented for and against availability, invariably based on a Universal Grammar defined solely in monolingual terms; failure to be like a monolingual means no access to UG. But it might be that monolingual native speakers are a special set of human beings with restricted input to only one language. Universal Grammar might well be present in L2 users in a fuller form than in monolinguals. This is developed in Cook & Newson (in press).

- the L2 user’s first language

What became apparent with the multi-competence formulation in Figures 2 and 3 was that the relationship between the two languages went in both directions. From the 1950s onward the influence of the first language on the second had been massively investigated, whether through Contrastive Analysis, Error Analysis, parameter resetting or other modes. Even if Weinreich had already talked about interference as 'those instances of deviation from the norms of either language which occur in the speech of bilinguals as a result of their familiarity with more than one language' (Weinreich, 1953, p. 1), people had not taken on board the influence of the second language on the first. The integration end of the integration/separation continuum may indeed keep the languages in watertight boxes. For the rest of the continuum, however, there is the possibility of considerable interpenetration in both directions.

In terms of syntax for example French speakers who know English react against French sentences using the middle voice Un tricot de laine se lave à l’eau froide. (*A wool sweater washes in cold water) compared to those who don't know English (Balcom, 2003). Japanese, Greek and Spanish speakers of English prefer the first noun to be the subject of the sentence in The dog pats the tree (translated into their respective languages) to a greater extent than those who do not know English (Cook, Iarossi, Stellakis & Tokumaru, 2003). If people who speak first languages without compulsory overt subjects (pro-drop) learn second languages with compulsory subjects, they are likely to tolerate subjects in their L1 more than monolingual native speakers, as found by Cook et al (2005) for Japanese learners of English; Tsimpli, Sorace, Heycock and Filiaci (2004) showed that ‘near-native’ Greek learners of English produced far more definite preverbal subjects in Greek than monolingual native speakers. L1 syntax is indeed affected by the L2 interlanguage, showing some form of a two-way interconnection.   

In terms of phonology, the first language of L2 users differs from monolinguals for plosive consonants such as /p~b/ or /k~g/ across pairs of languages such as Spanish/English (Zampini & Green, 2001), French/English (Flege, 1987), and Hebrew/English (Obler, 1982). There are differences in the intonation patterns in Dutch of Dutch people who speaker Greek (Mennen, 2004) and in German of German children who speak Turkish (Queen, 2001).  Phonological systems also are interconnected.

- the learner’s other languages

Those working in the developing area of multilingualism have made it increasingly clear that we can’t stop counting when we get to the second language; there may be a third, fourth, etc up to some indefinite number. It can’t be assumed that the L2 learner has just one language already in their minds. Leung (2005) showed that Cantonese L1 speakers with L2 English learnt French as L3 better than Vietnamese L1 speakers learning French as L3.  De Angelis (2005) compared learners of L3 Italian who were already either English L1/Spanish L2 speakers or Spanish L1/English L2 speakers; she found that, so far as transfer of function words to Italian was concerned, the L1 Spanish used 97% from their L1, 3% from their L2; the L1 English 19% from their L1, 19% from their L2; people who knew Spanish as either L1 or L2 used the Spanish third person pronoun el instead of the Italian lui, while people who knew French used French il; on the other hand English L1 with L2 French (a non-pro-drop language) tended to omit subjects in Italian (a pro-drop language) far less frequently than those with L2 Spanish (a pro-drop language). Not only the sequence of languages but also their typological closeness has big effects.

Clearly multilingualism research is going to show some fascinating new aspects of language learning. The relationships within the learner’s mind shown in Figures 2 and 3 get more complicated as more languages are added. Any model based on distinct separable languages in the mind is inadequate; we need a wholistic model like dynamic systems (Herdina & Jessner, 2002; De Bot, Lowie & Verspoor, 2005) to capture the L2 user’s mind in full.

- other aspects of the L2 user’s mind

The current area of bilingual cognition research looks at whether people who know second languages ‘think’ differently from monolinguals. In other words the L2 user differs from a monolingual native speaker in other areas of the mind than language. Athanasopoulos (2001) showed that Greeks who knew English had a different perception of the colour 'blue' from Greeks who did not; Athanasopoulos, Sasaki and Cook (2004) made a similar point about Japanese learners of English distinguishing two blue and two green colours differently from Japanese native speakers. Cook et al (in press) found that Japanese who had been in England longer than three years categorised objects more in terms of shape than Japanese who had been there less than three years. Athanasopoulos (2006) showed that Japanese learners of English move with level of English towards the English preference for counting objects rather than substance.

In addition there is longstanding evidence that knowing two languages affects the mind in numerous ways. Bilingual English/French children are better at the 'unusual uses' test (Lambert, Tucker & d'Anglejan, 1973); Spanish/English bilingual children have increased language awareness (Galambos & Goldin-Meadow, 1990). English children who learn Italian for an hour a week for five months learn to recognise words better than monolinguals (Yelland, Pollard & Mercuri, 1993). Hungarian children who know English are better at writing essays in Hungarian (Kesckes & Papp, 2000). Even some of the harmful effects of old age on cognition seem to be mitigated by knowing another language (Bialystok, Craik, Klein & Viswanathan, 2004).

The evidence is then accumulating that L2 users are not the same as monolinguals in terms of the first language, the second language or the rest of their mental apparatus. This is without going in to the differences in their uses of language and the range of situations in which they use language.

7. Conclusion

This paper has then tried to discuss how we think of L2 users and the languages they are learning which are affected by the decision to treat the L2 as an independent speaker of language. They raise problems of defining what we are talking about and of the political power vested in certain speakers and certain languages Most of them are still from being resolved. But they do demonstrate some of the complexity that we will have to  bear in mind in developing any theory of second language acquisition. But then why did we ever suppose SLA research was going to be simple? It has all the issues of linguistics, sociolinguistics, first language acquisition etc multiplied by several powers. Ideas like interlanguage and multi-competence are abstract approximations of the multifariousness of human language.


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