35. Do you still doubt ________ his new physical experiment?

　 A. whether he can manage　　　　　 B. if he will carry out

　 C. when he can finish　　　　　　　 D. that he will succeed in

34. It will be days ________.

A. till the international conference will end

B. since the international conference ended

C. before the international conference ends

D. then the international conference shall be ended

33. All the students stood up _______ the entrance of the teacher.

　 A. in　　 B. at　　 C. on　　 D. under

32. We have been told that under no conditions _______ the telephone in the office for personal affairs.

A. may we use　 B. we can use　 C. do we use　 D. we will use