I was raised trilingual: born in America to a Colombian dad and Lithuanian mom, so I speak English, Spanish, and Lithuanian. My Lithuanian has gotten a bit rusty since my younger days (mostly out of lack of practice--it's not a language you hear every day), but otherwise I'm fine with all three. Though I can't quite put my finger on it, I have no doubt in my mind that being raised with three languages has had a significant positive impact in how I think. And it's only as I've gotten older that I've realized what a gift that was. When I was young everyone would tell me that, but I didn't believe them because it seemed so natural!

If anything, knowing more than one language makes you better appreciate the commonalities of all langauges. For example English and Spanish are heavily rooted in Latin (English mostly in vocabulary), so you see a lot of words inbetween. Likewise Lithuanian also has a surprising amount of vocabulary lifted directly from Latin. Knowing all three and how these seemingly completely disparate languages are in fact related in many ways fills me with wonder.

I see several examples here of native speakers of two or more languages in the same language family (e.g., Indo-European). Our example at home is two older children (one who is grown up now, making his living as a hacker) who were brought up as native first-language speakers of both Mandarin Chinese and General American English. My wife is trilingual, growing up in a home that spoke Taiwanese (Taiwan dialect of Minnan Chinese), learning Mandarin as the sole language of school instruction, and learning English beginning in junior high school. Her higher education was in the United States, in the medium of English (of course). I grew up as a monolingual native speaker of General American English (although both my parents had had some foreign language instruction in school, in different languages, and each had living relatives born in the United States who were native speakers of non-English languages). I began learning Chinese, among several other languages, while at university, after learning German and Russian at school.

Oddly, the first language I ever spoke to my wife was actually Japanese, the usual Japanese greeting for a first-time meeting, "はじめまして. どうぞよろしく." Over the years, we have grown strongly to prefer speaking English with each other (from initially mostly speaking Mandarin with each other) because she finds it more congenial to speak what is really on her mind when speaking English. That's a cultural difference between American culture and Taiwanese culture--greater frankness in family conversations in America.

We were quite resolute in speaking Mandarin whenever we were together, whether living in the United States or in Taiwan, as our two older sons were growing up. I would speak to them in English if I was alone with one or both of them. They switched effortlessly from English to Chinese or back as my wife was present or not.

Literacy is HARD to maintain in languages in which the relationship between speech and writing is more remote than in English, as is surely the case in Chinese. I know many, many, many native speakers of Chinese who received their primary, secondary, and even higher educations in Chinese-speaking countries who forget how to write many Chinese characters if they spend a lot of time abroad. Computer input used to be nasty for Chinese, but it is coming along now even in American versions of Windoze. Literature is also more interesting to read if it is uncensored by the government, which gives English-language literature an enormous worldwide draw. But it is definitely life-enriching and thought-provoking to know two or more languages to reasonably high proficiency, and I have enjoyed spending the majority of my life able to communicate in Chinese.

One considerable advantage for the child who grows up bilingual is learning yet more languages as second languages when an adult more readily than do adults who grew up speaking only one language. By diligent study of linguistics, after having some foreign language study (German) that began in elementary school, I acquired enough Chinese to work professionally as an interpreter and a translator, and have enough reading German to be able to do research in that language, and smatterings of other languages. But all the native bilingual members of my family do much better than I do per unit of time in learning languages, so they have many choices before them as occasion arises to learn other languages for various purposes. That helps with second-language acquisition of an understandable pattern of pronunciation, too.

Very true! In my part of the Netherlands Dutch is the official language, but the much older and local other language is Frisian. What you see often is students talking Frisian to other Frisians and Dutch to non-Frisians even during the same group-conversation. They don't mean to, but can't help themselves. The "other mind" takes over seamlessly. I've seen Non-Frisians kindly ask if they can just talk Dutch only to hear them speak Frisian after about 20 seconds.

My wife (Polish) and I (British) are currently trying to have a child, and very much want to encourage our children to be bilingual.

I've spoken to a couple of people here who have one Polish parent, one non-Polish parent, and all seem to agree that it's easy enough to keep up the "Mum speaks Polish, Dad speaks language X" game for the first few years. Both said, though, that the real challenge was keeping interested during their teenage years.

That appears to be the challenge; thinking long-term, does anyone have any experience being raised in bilingual households? Did you keep interested past a certain age, and if so, how?

I love learning languages. I chose 12 languages and made a plan to learn each of them for a month, instead of watching TV. That way, in 5 years time, I will hopefully be very happy to have made this decision now.

Nothing impresses me more in people than their fluency in more than one language.

This is the one skill that is so raw and fundamental that it beats hands down everything else a person can ever learn, be it athletics, flying a jet or mastering business management. I worked with a tech support intern who was just starting in the business. He was white, in his early 20s and seemed like of an Irish descent. Then at some point he casually mentioned he spoke Chinese. What blew me away is how instantaneously my opinion of him changed. He jumped from being a smart guy, of which there's a metric ton, to someone I started to respect. Weird stuff, but perhaps it's just me.

Does the term bilingual limit itself to learning two language's fluently as a child? Or does it include learning a new language as an adult as well? And does it also demand that the person speak both languages with the repesctive native accent?

I've noticed that in some circles, people compete not on "What care do you drive?" but "How many languages do your kids speak?"

It would also be interesting to see how learning a non-phonetic alphabet, like Chinese or Japanese Kanji affects your brain. Learning tens of thousands of pictographs by heart is no easy feat, and I can tell you that bilingualism does not prepare you for that.

I think if you are not a native English speaker, you get a second language for free! And Indians in general have three languages, their local mother tongue, national language (Hindi) and English.

Most asian parents speak to their children in their native tongue, most likely the same for all immigrants, including hispanic. I know many friends whose kids spoke only their asian language until they hit preschool where they learned english. Kids pick up languages very fast when they are immersed in it.

I learnt French at school and did badly and then as an adult learnt French to a very high standard (I would call myself fluent and not bilingual). Something definitely happened to my brain as my French got really good; it was like I became two different people.

AskHN: The consensus is that each parent speaks his languge so as not to confuse the child. When the parents are taking to each other in the presence of the child, does each one talk to his own language? Or in that case it doesn't matter?

I'm not so sure about the statement that being bilingual reduces the vocabulary. If this is true, this would discourage me from raising a kid to speak two languages... after all, wasn't George Orwell's thesis in 1984 that removing words from the language removed the ability to think? Who would want to do this to a child? Does learning Latin as a second language, or Ruby indeed, restrict your vocabulary? I doubt it.