I speak six languages, and some of these were amazingly beneficial. This is the order in which I started speaking them:

1. English (I had a nanny from England, who somehow made me speak English before anyone else got me to speak anything else by the time I was two); it is still the language I do my best work in.
2. German (I spoke this mainly for the following 16 years, but have never used it at work or during studies, so I don’t sound very adult).
3. Latin (I was nearly pummeled to death with the damn thing, for seven years, two hours a day, and saw precious little value in it until I also started learning…)
4. French (which is based on Latin to such an extent, I could almost not take it seriously; my proficiency in French once secured me a great expat contract in China; the same thing happened with…)
5. Spanish (beautiful language that came to me almost in my sleep, that’s how close it is to Latin; I also would have learned Portuguese and Italian, having experienced this, but along came…)
6. Swedish (a language so conveniently located between English and German, and attached to a country that fascinated me so much, I jumped right into it and have stayed there ever since. It is my main language today, and speaking it enabled me to get hired and make my home in Sweden).