U.S. by birth, 25 years of frequent time in Australia, my observation not many people there speak a second language. Hardly fluent I can communicate in French, Mandarin, Vietnamese and Yiddish. In China and Vietnam, English is taught as a second language, and one of my Vietnamese friends is also fluent in French, but historically there is reason for that, when I was here in the ‘60s many Vietnamese had been taught French, the French forced their culture on the Vietnamese. Remember many immigrants to the U.S. from Europe did not teach their children their native tongue, very sad.

I am a US citizen by birth, but learned to speak German fluently in my twenties. To me, the learning of German causes me to compare English language to the structure of German, and helped me to understand the structure of language in general. I have always said that learning German was the best English lesson I ever had. I agree that learning a second language increases overall intelligence, as it causes one to develop new and more powerful cognitive schema.

UK French and a little cantonese. Some Yiddish and trying to learn Mandarin. Oh and I clearly need to learn English

Kenya born and bred. English, Swahili, French, Spanish - with a "stumbling" knowledge of Italian.

USA German poorly

It's a really nice thing to be able to think in someone else's language. I'm Irish and have some knowledge of the Irish language. The same with Spanish and this might seem irrelevant, old English. I feel I can put myself a little bit in the shoes of some other people even though I'm separated geographically, culturally and even in time.

Just a single example of the interesting things you find out about other people through their language. You can't break your arm in Spanish. To do that would be considered mad. Your arm is broken. That was on a Ted talk I watched recently.

I should answer my question as well. English is my first language. I learned some Spanish in High School. I have lived in Germany and could make myself understood for simple stuff and order in a restaurant. I had a good idea what the cop was yelling at me.... maybe. I lived in Japan and relied on the goodness of strangers and the magic of youth. I must have made my guardian angel work overtime more than once. I still swear in German and Japanese when under stress, though not as much Japanese anymore.

Research has shown that speaking more than one language decreases the onset of Alzheimer's and memory loss

I think it depends on where in the USA...most of the kids I grew up with speak more than one language...even now, most of my friends speak English and Spanish or English and Chinese...

English is my primary language but I also speak Spanish and some French. I am learning Mandarin but it is harder than I thought.

Good question. I have to say yes and no.

They say that the most effective learning is when you are a toddler. If you live in a house that speaks more than one language, you pick up on it at a young age. You don't worry about how the syntax is by the book. You just know how you should speak a sentence. Lots of old timers around here still speak Czech. I only know a few phrases, but I can understand a lot.

If you learn another language later in life, it is a lot harder. Spanish is my second. I am not fluent, but I can hold a conversation to someone that is a Spanish speaker, and doesn't know any English. It is harder to learn another language.