Bilingualism in adulthood

"Bilinguals acquire their two or more languages in childhood."

WRONG. 

Bilingualism in adulthood 

One can become bilingual in childhood, but also in adolescence and in adulthood. In fact, many adults become bilingual because they move from one country (or region) to another and have to acquire a second language. With time, they can become just as bilingual as children who acquire their languages in their early years (minus the native speaker accent). In general, people become bilingual because life requires the use of two or more languages. This can be due to immigration, education, intermarriage, contact with other linguistic groups within a country, and so on.

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