17. Global warming ________ if there weren't too much carbon dioxide in the atmosphere
. A. won’t happen B. didn’t happen
C. wouldn’t happen D. happened
18. Passengers __________ to smoke in the train.
A. are not allowed B. had not allowed
C. has not allowed D. will not allow
19. A powerful __________ off the coast of Indonesia sparked a three-metre-high and killed at least 113 people.
A. earthquake B. tornado
C. tsunami D. landslide
20. I ___________ a cup of tea before I left for my .
A. have B. have had
C. had had D. will have
21. “I'll give you your money back tomorrow.”
A. She promised me to give the money back the next day.
B. She promised to give me back the money the next day.
C. She promised to give me back your money the next day.
D. She promised to give you back your money the next day.