35. -----May I ask a question after class, Sir?

　 -----_______,　 but not during my lunch break.

A. I’m sorry　　　　　 B. Anytime　　　　　 C. Certainly　　　　 D. Go ahead

34. At the meeting they discussed three different ___ to the study of mathematics.,

A. Approaches　　　　 B. Means　　　　　　 C. Methods　　　　 D. ways

33. ______ this experiment is known to us.

A. Which to do 　 B. Whom to do　 　 　C. How to do　 　D. What to do

32. _______, we watched half a year’s food destroyed before our eyes.

A. Helplessly and sad　　　 　　　　　　　 　B. Helplessly and sadly

C. Helpless and sadly　　　 　　　　　　　 　D. Helpless and sad