1. It's not _____________(奇怪，惊讶) that he fail in the exam.

20. (　　 ) They didn’t start the work ___ their teacher came back.

　　　 A. until B. while C. as soon as D. if

19. (　　 ) He ___ back until the work ___ done.

　　　 A. isn’t; will be B. isn’t; is C. won’t be; will be D. won’t be; is

18. (　　 ) He ___ home ___ she was satisfied ___ his answer yesterday.

　　　 A. didn’t go; until; with B. wasn’t go; after; to

　　　 C. doesn’t go; before; with D. didn’t go; until; to

17. (　　 ) I won’t believe you___ I have seen it with my own eyes.

　　　 A. before B. until C. after D. when

16. (　　 ) The boy ___ to bed ___ his mother came in.

　　　 A. went not; until B. didn’t go; after C. went; until D. didn’t go; until

15. (　　 ) The meeting didn’t start___ everyone was there.

　　　 A. because B. until C. why D. if

14. (　　 ) Look, Mr. Li is ______ the visitors ______ our school.

　　　 A. show, around　　 B. showing, around　　 C. showed, around

13. (　　 ) Can you tell me _________ English well?

　　　 A. how to learn　　 B. what to learn　　 C. how can I learn