35. It was along the Mississippi River ______ Mark Twain spent much of his schoolhood.

　 A. how　　　　　 B. which　　　 C. that　　　　　　 D. where

34. --- If the weather had been better, we could have had a picnic.

　 ---But it________ all day.

　 A. rained　　　　 B. rains　　　 C. has rained　　　 D. is raining

33. If their marketing plans succeed, they _______ their sales by 20 percent.

　 A. will increase　　　　　　　　　 B. have been increasing

　 C. have increased　　　　　　　　 D. would be increasing

32. ______ that he was in great danger, Eric walked deeper into the forest.

　 A. Not realized　　　　　　　　　 B. Not to realize

　 C. Not realizing　　　　　　　　　 C. Not to have realized

31. What a pity! Considering his ability and experience, he _______ better.

　 A. need have done　　　　　　　　 B. must have done

　 C. can have done　　　　　　　　 D. might have done