Just to add to Richards already good answer. It's hard to explain what it means when it has been taken out of context, like richard said, your teacher said it; or maybe even be a line taken from a book. Here, context is critical as it would set the interpretation of everything that follows. context: the facts and circumstances of an event or situation. 在特定的上下文中理解一个短语的含意往往要更容易些。

Firstly, not a common saying...never heard this in my life. Secondly, it's already in English, so you can't say "translate into English"...you should say, "Can someone put this into more simplified Engilsh?" or something like that. Thirdly, I assume...though I cannot promise because I would say this is bad English...your language teacher told you this and his/her meaning was that only you have the ability to improve your language skills (and it needs you to move your lips so....). But let me state for the record, this is a strange sentence.....I wouldn't use it too much if I were you.

I think the sentence can be an old saying, meaning your future depends on what you say to people & how you say it. Another way of saying this is, think before you speak!

I can't improve on Richard's answer, but to provide further evidence that this is not a common saying ... a google search produced only a few Chinese language blog posts. No references to English language sites, literature or popular culture.

upstair handsome guy, good answer!