This post I wrote back in 2006 when my wife and I were talking about starting a blog on language learning for children. At the time, we were living in China with my daughter, who was just starting to speak, and a Chinese nanny. I think I intended to write more for the post, but since I've let it sit for so long, I can't recall where I was taking it. In any case, I'm posting it today, February 17, 2009, but keeping it's original date.
In the interest of full disclosure, we're not exactly the typical in terms of languages. In rough order of ability, Akiko speaks six (Japanese, English, Chinese, French, German, and Spanish) and I speak eight (English, Japanese, Chinese, Spanish, Portuguese, French, Italian, and German). Many say we both must be some kind of language geniuses, but I always argue against this assessment. What we had was not some blessed DNA, but rather a desire to learn languages and opportunities to do so which we took full advantage of. So while we have no qualifications in linguistics or the like whatsoever, we do know a thing or two about learning languages.
Our plan for our daughter and any other children that come along is for them to be fluent in multiple languages. English is an obvious first choice; even ignoring the fact that they'll be living in the States while they grow up and likely living there beyond that, English is of course the global language. And, of course, they'll need it to communicate with those in our family who haven't spent quite as much time learning other languages. Japanese is another no-brainer; they'll need it to communicate with the Japanese side of our family. Beyond these, we're incorporating two more languages: Chinese and Spanish. China's economic rise gives the Chinese language more and more import, and this will continue long into our children's lifetime. Spanish has become the unofficial second language of the United States and speaking it will be an advantage in a wide range of professions in the States.
There's also some strategy here if they want to branch out to other languages. Picking up another Germanic language—German, Dutch, Nordic languages, etc.—will be made at least a little bit easier by knowing English. Learning the other Romance languages—Italian, Portuguese, French, etc.—is much easier when you already know one. Learning Chinese—i.e., Mandarin—makes it easier to learn any of the other Chinese "dialects" (I put that in quotes because the they're usually as different as or even more different than the Romance languages which for some reason are not considered "dialects" of Latin). And learning Japanese can help with Korean.
If any of our kids branch out into any other language groups—Slavic languages like Russian, Semitic languages like Arabic, etc.—they won't get as much help from the languages they already know but they should already have the "hardware" for new languages. The hardware/software analogy is one I used often when describing my take on learning languages. With each new languages you learn, you're developing your language-learning facilities, i.e., the hardware. Grammatical rules, vocabulary, writing systems, accents, etc., are all just the software. The more languages, you learn, the better you develop your "hardware" and the more easily you can "install software". So if the language hardware is already top of the line, any languages they decide to take on should be made easier.
Of our four languages, we've got no convenient way to teach her Spanish at this point, so that's being held off on until we get back to the States and have some money to put towards it.
Our basic plan is creating the best environment for learning the language. We've hired a Chinese nanny to care for our daughter this year. She takes her our and she plays with all the Chinese kids in the neighborhood. Akiko is with her plenty as well, so Japanese is covered. I'm often busy at work and don't get to see her as much, so I always make a point of just running my mouth off in English when I'm with her, reading books to her, and simply teaching her what things are called.
So perhaps it's unsurprising that right now Chinese is her strongest language. It's generally her language of first choice when she proactively speaks, although it depends on which language she used to learn the word. For example, she learned to jump on the bed with me, so "jump" is in English. Japanese would be the next strongest, and English the least. However, in all of the languages she understands much of the same things when we say them, even if she doesn't proactively say them herself.
Several examples have already emerged of her knowing the words in multiple languages. "Dog" is one example. She recognizes and can say it in English, Japanese (wanwan), and Chinese (gǒu). She first learned it in Japanese, and that continues to be the most common to come out of her mouth, but Chinese has come more and more often as she's used gǒu with the nanny. She generally will only say "dog" when I first use it, but then she knows to use that instead of the other two. "Eat" is another example.