It is impossible to learn every language on Earth.
only speak the language you want to learn and hang around people that speak that language.
I think it is when you learn a second language. Like, if you speak English as your first language, then learn to speak Spanish fluently, you acquired Spanish as your second language.
the most widely spoken language is english so that is good to learn if you don't know it already. spanish is also a good language to learn because it is common and the most people on earth speak chinese so that is also good.
You should get a translator because every language has idioms and slang that might not make sense to you even if you learn the language.
GO TO COLLEGE
You must first learn the language
You study books, listen to CD's, and speak with others in that language.
No. No one speaks every major language.
Essentially, everyone speaks with an accent. We only say its an accent because its different from how we talk. So yes, because everyone on earth speaks with an accent. If they speak in a language other than their original, that is. Unless they learn the second language at a very young age.
"Semitic" is the name of a language family, not one language in particular. So yes, you can learn to speak Hebrew or Arabic, and would be able to speak a Semitic language, but you would not be speaking a language called Semitic.
Russian people can learn to speak Japanese. There really are no cultural boundaries limiting attempts at becoming a bilingual speaker.
Only if they learn it as a foreign language.