—Mike felt sad because he failed his exam yesterday. —I’m sorry to hear that. Let’s ___.
——How long have you worked here? ——__________________.
Peter ________ to help our math teacher carry books yesterday.
——What’s your mother? ——She_________ a teacher, but now she is a doctor.
——How long has his father ________London? ——For two weeks.
This kind of CD-ROM is very popular. Why not buy one before it___________? A. comes out B is come out C. is sold out D. sells out