Great idea, lousy execution. Besides the problems others have already mentioned, it's slooooooooowwwwwwww. Also, two very serious fundamental problems:

1. Many of your translations are wrong. I took the Spanish lesson. All of the Spanish verbs are infinitives, but the English translations are all gerunds.

2. Learning a language one word at a time doesn't really teach you the language. You need to learn more than just vocabulary, you need grammar, conjugations, declinations, etc.

But I hasten to add, the idea of a language tutor that keeps track of what you know and only drills you on the stuff you don't is a really good one and very promising if you can actually make it work. But it's not an easy problem. (For an aspiring entrepreneur this is a good thing. If it were easy someone else would have done it already.)