The jobs available to a modern languages major are quite limited. You would either end up working as a translator / interpreter, teacher, or something completely unrelated. That's not to say studying languages is worthless, though -- quite the opposite really. I recommend that you major in something that will give you broader career prospectives while doing a minor (or perhaps a double major) in a modern language.
One thing you might want to consider would be taking a semester or a full year off to work, travel, and gain life experience so you can figure out exactly what you want to study. In fact, I really recommend that if your situation allows it. Just remember that you'll have to go back to school eventually

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