35. --- My son is ______ to be seen. Where has he gone?　

--- I think he ______ in the building.

　　 　A. nowhere; must be hiding 　　B. nowhere; must be hidden himself

C. anywhere; hides　　　　　 　D. everywhere; hides himself

34. Tom was successful in the experiment and we sent him an e-mail, ________ him on his success. A. celebrating　　　　 　B. congratulating　C. celebrated　　D. congratulated

33. ______ I admit that the problems are difficult, I don’t agree that they cannot be solved.

A. Until　　　 B. While　　　 C. As　　　 　　D. Because

32. -The experiment is of particular importance.

　 -I see. We will carry on with it ________ we can get enough money.

　A. unless　　B. though　　C. whether　　D. until

31. ______ , I have never seen anyone who's as capable as John.

A. As long as I have traveled　　　　 B. Now that I have traveled so much

C. Much as I have traveled　　　　 　　D. As I have traveled so much