—I saw Mr. Green at school this morning. —No, it _____ him. He flied to Canada last week. A. can be B. must be C. can’t be
—Do you think the students need to have lunch at school? —____. It’s good for them to save time.
—Will you please ____ so much noise, Dongdong? —Sorry. I won’t.
I don’t know ____ or not he is right.
—Would you like to come to our food festival? —____
The teacher asked me____________.