It was along the Mississippi River _________ Mark Twain spent much of his childhood.
| A．how | B．which | C．that | D．where |
16. I returned home with some roses and only then __________ find my favorite vase missing.
| A．I did | B．did I | C．do I | D．I do |
15.She was lifting handfuls of fine sand and letting it pour __________ her fingers.
| A．across | B．in | C．through | D．into |
— Excuse me. Do you happen to have change for a 50-pence piece?
— __________. I’ve just used up all my coins.
| A．I don’t believe so | B．I can’t agree more |
| C．I’d rather not | D．I’m afraid not |
. With examinations coming immediately, you ________ the Internet last night.
| A．mustn’t surf | B．shouldn’t surf |
| C．couldn’t have surfed | D．shouldn’t have surfed |
-- Why didn’t you come to see the film with your parents last weekend?
-- I _____ my lessons for the month- exam.
| A．was preparing | B．prepare | C．prepared | D．have prepared |