Important Languages

I'm planning on travelling very soon. It's been a long time since I have left the United States. So, in order to prepare myself for my future travels, I am making a list of the languages I either need to brush up or learn, so that my travel experience can go as smoothly as possible. I can't expect everyone to be able to speak to me in English, just because I carry a US Passport.

1. French - The language of France, Monaco, Quebec, Switzerland, part of Belgium, Luxembourg, various former colonies in Africa and the Caribbean.
2. Spanish - The language of all of Latin America except Brazil, as well as Spain and Andorra.
3. German - The language of Germany, Austria, Switzerland, as well as a well-studied language in other countries nearby.
4. Arabic - The lingua franca of all of North Africa, the Middle East, and Muslim countries everywhere.
5. Mandarin - The most-spoken language in the world, useful in China and in nearby countries.
6. Portuguese - The language of Portugal, Brazil, Angola, and Mozambique, as well as various former colonies.
7. Russian - The language of Russia and a second language in many places formerly behind the Iron Curtain.
8. Italian - The language of Italy, San Marino, and Switzerland.
9. Greek - The language of Greece and Cyprus.

Fortunately, I have books and I have signed up for an account on Mango, which includes all of these languages and more.