20.Mr.Black is very happy because the clothes made in his factory have never been________.

A.popular　 B.more popular　 C.most popular　 D.the most popular

19.Excuse me I________I was blocking your way.

A.didn’t realize　　 B.don’t realize　　 C.haven’t realized　　 D.wasn’t realizing

18.-Can I help you? Are you looking for anything in particular today?

　 ---_________We’re just looking.

　　　 A.　　 Yes please　　 B.No, thank you　　 C.Yes ,you can　　 D.No, you needn’t

17.I’m afraid Mr. Harding_________see you now. He’s busy.

’t　 B.mustn’t　 C.shouldn’t　 D.needn’t

16.I refuse to accept the blame for something________was someone else’s fault.

A.who　 B.that　 C.as　 D.what