Past tenses in chinese There are 3 friends who haven't met for some time. Freddy, Charley and Tony.One day they meet again. Freddy knows that Tony has recently started a course of Chinese Language. He knows that Charley, while at University, 10 years ago, had also studied Chinese. So Freddy asks Charley: "how long did you study Chinese for, when you were at university"? Freddy asks Tony: "how long have you been studying Chinese for"? In the case of Charley, he knows that Charley started and finished a language course in the past. But it doesn't know how long it lasted. In the case of Tony, he knows that he started the language course in the past, and that he's still studying it. But he doesn't know when he started it and therefore for how long he's been studying Chinese. How do you translate the two questions? "how long did you study Chinese for, when you were at university"? "how long have you been studying Chinese for"? Perfectly understanding Chinese past tenses has become my obsession! :-) Thank you all!