现在进行时:A -what are you doing? B -I'm watching a movie. 现在完成时:A -Have you finished your homework yet? B -Not yet, but I will finish it. 一般过去时:A -When did you borrow the book from the library? B -The day before yesterday. 一般现在时 A -You are a student,so you must focus on the study. B -Mom,I konow what to do. (完成时分为现在完成、将来完成、过去完成.就是不知道你说的什么一般完成)