The amount of time that children spend listening to each of their languages, be it their parents’ two languages in bilingual families, or the family and the community language, has a huge influence on how quickly they develop their language skills. So, quantity matters!
Does quality matter, too? This is less clear. Partly this is because less research has been conducted on this topic, and partly because of the huge range of experiences that children face when growing up bilingual. Quantity is easy to define and measure. By contrast, measuring quality is hard: there are many different factors that could make the language experience of one bilingual child qualitatively different from the language experience of another.
This study tried to look at some of the factors that make up the qualitative experience of bilingual children. Twenty-nine 25-month-olds from Florida, who were exposed to both English and Spanish on a daily basis, were involved in the research. Parents informed researchers about how many words their children use, and what types of sentences they produce (simple or more complex), in both English and Spanish. For seven days, they also kept a diary of all the child’s activities, including the language(s) spoken during each activity, and the number of different speakers of each language the child came in contact with. Using this information, the researchers first of all confirmed that the more exposure to English, the more words and sentence structures used in English, and similarly, the more exposure to Spanish, the more words and sentence structures used in Spanish (again, quantity does matter!).
But over and above quantity, some quality factors also made a difference to the child’s knowledge of words and structures. Listening to different people (e.g., not just mum or dad, but also grandparents, or a babysitter) speaking a language had a positive effect. And especially if those people were native speakers of the language, and could not speak the other language (so that the child could not switch to the other language when talking to them), the child tended to know more words and structures. This means that if two children of the same age received the same amount of exposure in one language, the child who received that exposure from listening to a larger number of different people (particularly native monolingual speakers) would probably know more words and sentence structures in that language. However, one factor that did not matter was how often English and Spanish were used together during the same activity. So, mixing languages does not seem to be a problem.
These results should be taken with a pinch of salt, because 29 families is not a big number, and because for some of these families English was both the community language and the language of one of the parents, while for others it was only the community language. This might matter too! But the study still shows that quality and quantity are both important in shaping how quickly children grow bilingual.
Place, S., Hoff E. (2011) Properties of Dual Language Exposure That Influence 2-Year-Olds’ Bilingual Proficiency.
Child Development, 82 (6), 1834–1849. DOI: 10.1111/j.1467-8624.2011.01660.x
