21. ________ the deaf children, the young lady has little time to care for her own daughter.

A. Devoted to teach B. Devoted herself to teach

C. Devoting herself to teaching D. Devoting to teach

22. ---I’d like to go on a journey to Africa because I can see a lot of wild animals there.

---Yes, it’s a region ___________ in wildlife.

A. enough B. abundant C. luxurious D. splendid

23. ------.I'm sure you'd rather she returned home, ____?

A. wouldn't you B. shouldn't you C. didn't she D. couldn't you

24. ______I feel sorry for those who have met with the trouble, I can’t really do very much to help them out.

A. Unless B. As C. While D. Even