The Linguist

30 The Linguist Vol/60 No/2 2021 thelinguist.uberflip.com OPINION & COMMENT JÜRGEN M MEISEL Bilingualism in early childhood has long been a controversial issue. Whereas some fear it might entail risks for children's linguistic or cognitive development, others regard it as only beneficial. More than 100 years of research strongly supports the latter view. Studies have shown that children acquiring two languages simultaneously can differentiate between them from early on, attaining native competences in both languages. But what happens when children are exposed to more than two languages from birth? Multilingualism is a well-established phenomenon in many parts of the world, and due to migration a steadily increasing number of children grow up in multilingual settings. While we can answer with confidence questions about the benefits or risks of bilingualism, that is not always the case here. We do know that the human language faculty enables children to acquire three or more languages simultaneously if two conditions are met: acquisition onset happens early in life and there is sufficient exposure. But what is meant by 'sufficient'? Children at an early age are undoubtedly capable of acquiring some linguistic knowledge under less than optimal conditions. However, the problem is in specifying the minimum amount of exposure necessary for the development of native or near-native competence in three or more languages. Understandably, parents are looking for a specification of the minimum amount of exposure required. Yet linguists and psychologists are reluctant or unable to provide clear answers. One reason is that studies of the simultaneous acquisition of three or more languages are scarce. Moreover, the kind of investigation most likely to shed light on this issue is ruled out for ethical reasons, since it would compare groups of children with decreasing access to the target language in order to determine at which point acquisition failure happens. Another major obstacle is the lack of a benchmark value because it is extremely difficult to assess the amount of input that monolingual children 'normally' receive. Simply counting words or sentences uttered in the presence of children will not do, because only child-directed speech – input presented in meaningful interactions – enhances linguistic development; overhearing conversations or watching television does not. Studies measuring the amount of speech that monolingual children hear during one day have shown that it varies enormously. In some families toddlers were exposed to ten times the number of words as children in other families. Importantly, they all seem to receive more input than is minimally required. This does not mean that acquisition research has nothing to offer parents raising children multilingually. Valuable insights are available, even if the empirical basis is limited. One such insight is that the quantity of input that multilinguals receive in each language can be equal to – or larger than – that of bilinguals or monolinguals if parents speak to them frequently. The challenge is to determine the point at which decreasing amounts of input affect the quality of the acquired knowledge. Studies investigating how children cope with significantly reduced access to the target languages reveal a somewhat blurred picture, but it seems that it is possible to acquire a native competence if exposure amounts to 20-30% of weekly interactions. Development under these conditions happens typically at a slower rate, but the level reached can be the same. Trilingualism is thus not a problem. In fact, simultaneous acquisition of four languages is also possible if exposure to each of them amounts to approximately 25% of child- directed speech. I must add that not all multilingual children attain the same level of knowledge and proficiency in all their languages. Further, some may refuse to use one of them, although they understand it. Receptive multilingualism means that use of acquired linguistic knowledge is avoided, but it will develop further and can be activated at a later time. Parents should nevertheless establish a language hierarchy, according to the needs of the child and the family, thus making sure that native competence is attained in the one ranked highest. Jürgen Meisel's book Bilingual Children: A guide for parents was published in 2019 by Cambridge University Press. Jürgen M Meisel is a Professor emeritus of linguistics at the universities of Hamburg and Calgary; jmm@uni-hamburg.de TL Can children learn to speak three languages fluently? En famille © SHUTTERSTOCK

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