> They want to teach their son both, but can’t. Yes, they can. It is very easy. Each parent only speaks to the child in their own language. That is all. ----

> They want to teach their son both, but can’t. Yes, they can. It is very easy. Each parent only speaks to the child in their own language. That is all. ---------------- The children of immigrants lose languages because their parents are ignorant of basic pedagogy (in most cases the parents just raise the kids in English, then get mad they don't magically know the language they were barely exposed to.) Presumably, they think they should have full conversations with each other in Korean and Chinese to expose the kid - however as a baby understands that they speak all 3 languages, the baby would default to the most common one (English). The key here is to establish boundaries of language use e.g.: "I speak Chinese to dad. I speak Korean to mom." The parents should not respond to the child in English - they have to preserve the boundary to encourage the kid to use the other languages. If one of them uses English with the child, it will greatly weaken or ruin the effect. Adding cartoons, other speakers etc. for these languages helps but isn't as fundamentally necessary as this. You can even add multiple nannies which only speak their own language to the child. (There is some amount of regular exposure needed, but that's not an issue for 2 parents.) The child will pick up English from other children and tv.