There is no deadline. Children can learn two languages from birth, or start a second one later. Here is what language experts say about both approaches.
Any age works. ASHA (the American Speech-Language-Hearing Association) describes two approaches: "Use two languages from the start", or "Use only one language at home", in which case "your child can learn the second language when he or she starts school." Starting early is natural for children who hear two languages at home.
Common when parents speak different languages, or when the home language differs from the community. Children build both vocabularies side by side.
One language at home, and the second at preschool or school. ASHA notes this works too.
ASHA also says that learning two languages does not cause speech or language problems: "Children all over the world learn more than one language without developing speech or language problems."
For babies and toddlers, a second language starts with words: naming the same cow, ball and tree in both languages, in everyday life, books, songs and short picture games. In EveryLingo every picture can show the word in two languages at once, each with its own sound.
There is no single best age. ASHA describes using two languages from the start, or one language at home and the second "when he or she starts school". Both work.
Yes. Many children grow up with two languages from birth. ASHA says learning more than one language does not cause speech or language problems.
No. ASHA notes children can learn the second language when they start school.
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