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Bilingualism and the acquisition of L2

Antonio Alarcon

University of Warsaw



Being bilingual is commonly viewed as the ability of an individual to have total control over two languages. Provided the fact that this definition makes the concept of bilingualism appear simple, there is much more underneath. The concept of bilingualism concerns the individuals who are able to communicate efficiently in two languages or more. Hence, there are several studies and theories of language learning whose aim is to determine what bilingualism really is and how to achieve such an ability. This dissertation answers these questions and presents bilingualism in all its complexity.



The term bilingualism appears very often when referring to language in general. Even though bilingualism is a phenomenon which has existed for many centuries already, research into this phenomenon is considered relatively new. It was not until the twentieth century that scientists began studying it. The phenomenon itself is more complex that it might seem at first sight.

The process which a person experiences while acquiring the first language differs totally from the second language acquisition process (except the children who acquire two languages simultaneously at an early age) and there are several theories providing an explanation to the mechanism involved in the acquisition of a new language.

Far from being a phenomenon which can easily be explained, bilingualism is much more than that; by this we could deduce that the acquisition of a language is subjected to several factors, which we will discuss in greater detail.



There are different points of view with regard to a suitable definition of bilingualism. ‘‘In the popular view, being bilingual equals being able to speak two languages perfectly; this is also the approach of Bloomfield (1935, p. 56), who defines bilingualism as the native-like control of two languages’’ (Hamers & Blanc, 2000, p. 6).

However, it is a common mistake to think of bilingualism as the capacity of a speaker to be fully competent at a native-like level in two or more languages. The concept of bilingualism is actually defined as the ability of an individual to speak two or more different languages with a decent level of fluency. By this, it is implied that bilingualism does not mean speaking two or more languages equally, and at the same degree, for there are different types of bilingual individuals and not all of them fall into the same category.

Haugen (1953, p. 7) states that “bilingualism is understood (. . .) at the point where the speaker of one language can produce complete meaningful utterances in the other language”. Therefore, it is implied that it is not exclusively necessary to be flawlessly fluent in an additional language to be considered bilingual.

Furthermore, coming across a bilingual speaker who has acquired two or more languages equally at a native-like level is unusual. Most individuals are more proficient in one of the languages. The language in which a speaker is more competent is called ‘the dominant language’. The reason why bilingualism is a complex term to define is that language itself is complicated. It is practically impossible to identify how proficient a person is in a certain language; when it comes to knowledge, one can just make rough approximations, for it is impossible to access one’s mind to determine how skilled a person is in speaking a certain language.

If we were to compare the native-like proficiency of monolingual individuals with the native-like proficiency of bilingual individuals, we would be left with a very small percentage of ‘perfect’ bilinguals (Lam, 2001, p. 93), which would be those who are able to speak their two languages at the same level and with impeccable fluency. They are called ‘balanced bilinguals’ (Hamers & Blanc, 2000, p. 27). The remaining bilingual individuals would be tagged as ‘imperfect’ bilinguals, according to this rule. Based on this assumption, we have to agree that the term bilingualism should not only apply to those individuals who are fully competent in both their languages, for it would be wrong to suggest that those who are able to communicate efficiently in two languages (despite not having a perfect fluency) are monolingual. Thus, the rate of balanced bilinguals being apparently reduced, one might expect the total acquisition of a second language to be a complicated achievement.

The phenomenon of bilingualism is present in every country, with different numbers of bilingual individuals depending on the place. In the US, about 20% of the population are bilingual (about 55 million inhabitants) (Nelson, 2013), while in Canada the percentage of bilingual speakers is 35%, as stated by Grosjean (2010). Approximately more than half of the European population (54%) are able to speak an additional language (Eurobarometer 386, 2012, p. 5). That leaves the remaining 46% of the population who are not yet competent enough to communicate efficiently in a second language. In countries such as Luxembourg, Sweden, Denmark and the Netherlands, nearly all inhabitants are able to speak two languages (one of them being their own mother tongue). In Europe, English has an exceptional importance. In 2012, the Eurobarometer gathered the following information: “At a national level English is the most widely spoken foreign language in 19 of the 25 Member States where it is not an official language (i.e. excluding the UK and Ireland)” (Eurobarometer 386 2012, p. 5). In other countries, such as India or Singapore, it is totally natural for a child to speak two or three languages; they are referred to as multilingual speakers or polyglots.

As it can be appreciated, knowing more than one language is not a strange feature, but a potential characteristic of any human being. With this phenomenon being so widespread, one might wonder how bilingualism emerges and develops.


Second language acquisition and its theories

Linguists and psychologists have always wondered how it is possible for a human being to become bilingual. The process which occurs while another language is added to the linguistic abilities of an individual remained a mystery for a long time. One of the most frequently asked questions concerns the processes which occur in the brain of a bilingual individual while he or she communicates. This question cannot be answered without analyzing the different theories of second language acquisition and without explaining the two key concepts, i.e. simultaneous bilingualism and successive bilingualism. Simultaneous bilingualism applies to those individuals who acquire their two languages at the same time (i.e. simultaneously) while the latter concept is applied to those individuals who acquire their two languages one after another (i.e. successively) (Lam, 2001, p. 95). However, making a clear distinction between simultaneous and successive bilingualism has always been difficult. “DeHouwer (1995) has proposed the stringent cut-off of exposure to two languages within one month of birth, while McLaughlin (1978), in an early review of bilingual acquisition research, proposed the much more lenient cut-off of exposure to two languages before 3 years of age” (Genesee & Nicoladis, 2008, p. 325). In successive bilingualism, the process of learning the second language (referred to as L2) is known as second language acquisition (i.e. SLA).

There are different theories explaining the SLA. These theories vary depending on the subject. We shall be aware that learning L2 as an adult is different from learning it as a child, as there are differences between L1 and L2 learning. According to Bley-Vroman (1996, p. 718), “while child language development theory must explain invariant “success”, foreign language learning theory must explain variation and lack of success”. Therefore, theories applying to the acquisition of a language may differ whether implying the learning of a child or an adult.

Theories regarding the acquisition of L2 must hold consistent evidence and they have to fit in real-life situations. Moreover, they should treat language not only as a conscious process but also as a subconscious one; including not only environmental factors (social and cultural surroundings) but also contextual ones (depending on the context). An example of a reasonable theory is that of Krashen. As stated by Schmidt (1990, p. 130), “Krashen (1981, 1983, 1985) has elaborated a theory that rests on a distinction between two independent processes, genuine learning, called ‘acquisition’, which is subconscious, and conscious ‘learning’, which is of little use in actual language production and comprehension”. The theories of SLA (they also function for the acquisition of the first language) are divided into three principal groups: nativist theories (including input-based theories), environmental theories and interactionist theories (Luque 2012).

Nativist theories claim that children possess innate capacities to learn any language in the world (Luque 2012). One of the best known theories states that children are born with a language acquisition device (LAD), which grant them the ability to acquire and use any language in the early years of life. This approach was first proposed by Noam Chomsky in 1960. This theory explains why there are individuals who encounter more difficulties when learning a second language which they did not know during their first year of life, for the mechanisms involved in language learning are more reinforced in infants. However, this also applies to the acquisition of L1. There are cases in which a child is not able to learn its mother tongue during its first year of life due to abuse or if affected by unnatural conditions. Such was the case of Isabelle, a girl who was kept in a dark room with the only company of her mother, who was deaf-mute. When the girl was found at the age of six, she could not emit meaningful utterances and professionals tried their best to help Isabelle obtain her linguistic abilities. At the age of fourteen, with proper care and training, Isabelle was reintegrated in the society and her speech improved, but it never reached the level of that of her colleagues (Millero, 2013).

Input-based theories overlap with the group of nativist theories. An example of an input-based theory would be Stephen Krashen’s Monitor Theory, which is one of the most valuable approaches (Luque 2012). “Krashen’s Monitor Theory claims that two systems are present in SLA: the acquired system which results from subconscious knowledge of SL grammar as in L1 acquisition, and the learner system, which is conscious and results from classroom instruction” (Saraswati, 2004, p. 36). His theory is based on five hypotheses:

1.Acquisition-learning hypothesis

It identifies two different means of learning a language. The acquisition process would be subconscious and natural, equal to the process taking part in the acquisition of language in children. The learning process would be conscious and it would focus on formal instruction, such as the learning of grammar rules (Luque, Topic 5: Models and Theories That Explain L2/FL Acquisition).

2. Natural order hypothesis

This theory states that the learning of rules in the L2 is acquired in a certain and precise manner, driven by innate abilities (Luque 2012).

3. Monitor hypothesis

The Monitor Hypothesis makes reference to the connection between learning and acquisition. “According to Krashen (1985), the acquisition system is the utterance initiator, while the learning system performs the role of the ‘monitor’ or the ‘editor’” (Girón, 2013, p. 29). Therefore, the monitor would edit and correct the learner during the process of acquisition.

4. Input hypothesis

The Input Hypothesis explains the way language is acquired by the learner. The L2 is acquired through input. Such input has to be above the level of the learner but it has to be sufficiently understandable or comprehensible; if it is too simple (i.e. less than level of the learner), the learner loses motivation and the input becomes ineffective. According to this theory, L2 is acquired through the assimilation of inputs, but this is only possible thanks to innate abilities (Luque, 2012).

5. Affective filter hypothesis

This hypothesis suggests that certain factors have an effect on the process of the SLA. Such factors can interfere with the process of learning and can accelerate of slow down the process. The bigger the affective filter is, the less the learner will progress. Elements such as low self-esteem or the absence of motivation enlarge the filter, causing input not to function correctly on the learner (Luque, 2012).

On the other hand, environmentalists claim that experience plays a much more important role in learning than innate conditions (Luque, 2012). An outstanding example of an environmental theory is that of Parallel Distributed Processing (PDP). PDP opposes innate abilities and states that learning occurs due to input. It consists on the reinforcement of neural connections. PDP means that an individual learns a language by means of rules rather than association. The brain is said to have neural connections (or nodes) and the stronger these connections are, the faster an individual would recall the necessary information (Luque, 2012).

Lastly, there are interactionist theories. These theories are considered to be more consistent than environmental and nativist theories, for they explain the acquisition of language including both environmental and innate factors. One of the most important examples is Klein’s model (1986), which distinguishes three different dimensions in the acquisition of language (Luque, 2012). These dimensions are: linguistic faculty, propensity and access. Linguistic faculty refers to the capacity of an individual to learn a language (e.g. aptitude). Propensity makes reference to an instinctive predisposition to learn a language (e.g. motivation). Finally, access involves being in contact with the language by means of input or a frequent usage of the language, i.e. having opportunities to learn the language. According to interactionists, these three conditions are essential for the acquisition of a language. However, for the process of acquiring a language to happen, three more conditions are needed: structure (the order in which elements are learnt), sequence (the time in which the learner acquires a language) and the final state (it may not be as successful as the learner wishes).

Our own mother tongue plays a fundamental role when learning the L2. An individual learning a second language at a later age will not be able to acquire the features of L2 completely. Instead, the phenomenon of interlanguage occurs during the learning process. “The term ‘interlanguage’ was most persuasively introduced and developed into a set of testable hypotheses by Selinker (1972)” (Berns, 2010, p. 135). Interlanguage refers to an intermediate process between an individual’s L1 and L2. According to Selinker (1972), learning L2 is not equal to learning our first language. While during the learning process of our mother tongue we use the so-called ‘child language’, in L2 we observe the presence of interlanguage. During the acquisition of L2 we utilize mechanisms that are not present in the learning of L1. Therefore, the learning of L2 is influenced by the influence of our mother tongue, and individuals cannot apparently acquire a second language at a native-like level unless the learning process occurred during early ages, for there will always be small differences (which may be imperceptible for the majority) even in those bilinguals who learnt their L2 at a later age and who have an apparent perfect accent.

Selinker (1972) connects the phenomenon of interlanguage with fossilization. The phenomenon of fossilization refers to the impossibility of the full acquisition of a second language, missing some of its features. “Fossilization is a permanent phenomenon. In other words, it inevitably appears during the acquisition of a second language in the vast majority of cases” (Díaz-Ducca, 2013, p. 66). Fossilization is also referred to as incompleteness (Han & Odlin, 2006, p. 22). According to Selinker (1972), there are two explanations to this phenomenon. One is that the mechanisms taking part in the learning of L2 are different from the ones functioning in the acquisition of L1. Another theory is that the learning process of L1 and L2 might be affected by the same mechanisms but the process is hampered by unpredictable factors. According to Tarone (1994) (as quoted in Han, 2004, p. 18), “A central characteristic of any interlanguage is that it fossilizes – that is, it ceases to develop at some point short of full identity with the target language”. Therefore, the connection established between fossilization and interlanguage seems to be a true phenomenon, and interlanguages seem to never be able to develop to their maximum extents i.e. perfect L2 acquisition.



Special studies

  1. Berns, Margie — Keith Brown. 2010. Concise Encyclopedia of Applied Linguistics. Amsterdam: Elsevier.
  2. Bley-Vroman, Roman. 1996. “What we have to explain in foreign language learning”, Behavioral and Brain Sciences 19: 718-718.
  3. Bloomfield, Leonard. 1935. Language. London: George Allen and Unwin Ltd.
  4. DeHouwer, Annick. 1995. “Bilingual language acquisition”, in: P. Fletcher — B. MacWhinney (eds.), 219-250.
  5. Genesee, Fred — Elena Nicoladis. 2008. “Bilingual First Language Acquisition”, in: Hoff, Erika —Marilyn Shatz (eds), 324-342.
  6. Hamers, Josaine — Michel Blanc. 1989. Bilinguality and bilingualism. Cambridge: Cambridge University Press. (Revision and translation of “Bilingualite et bilinquisme,” 1983, by same authors).
  7. Han. (2004). Fossilization in adult second language acquisition. Clevedon: Multilingual Matters.
  8. Han — Odlin. (2006). Fossilization: Can grammaticality judgment be a reliable source of evidence? In: Han and T. Odlin (Eds). Studies of fossilization in second language acquisition (56-82). Clevedon, UK: Multilingual Matters.
  9. Haugen. 1953. The Norwegian language in America: A study in bilingual behavior. Philadelphia: Univ. of Pennsylvania Press.
  10. Klein, Wolfgang. 1986. Second Language Acquisition. Cambridge [Cambridge shire]: CUP.
  11. Krashen, Stephen. 1981. Second Language Acquisition and Second Language Learning. Oxford: Pergamon Press.
  12. Krashen, Stephen. 1983. ““Newmark’s “ignorance hypothesis”” and current second language acquisition theory’”, in: Larry Selinker — Susan Gass, 135-153.
  13. Krashen, Stephen. 1985. The Input Hypothesis: Issues and Implications. London: Longman.
  14. Lam, Agnes. 2001. “Bilingualism”, in: Ronald Carter — David Nunas (eds.), 93-99.
  15. McLaughlin, Barry. 1978. Second-language Acquisition in Childhood. Hillsdale, N.J.: L. Erlbaum Associates.
  16. Saraswathi, V. 2004. English Language Teaching: Principles & Practice. Orient Longman Private Limited.
  17. Selinker, Larry. 1972. “Interlanguage”, International Review of Applied Linguistics 10: 209-231.
  18. Tarone, Elaine. 1994. “Interlanguage”, in: R. Asher (ed.), 4: 1715–1719.

Online references

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Published: 2017-06-27