People _____ to set off firecrackers in some areas of Shanghai for several months.
A. aren’t allowed B. weren’t allowed
C. won’t be allowed D. haven’t been allowed
Scientists warn that El Niño _____ the world this coming summer.
A. damaged B. had damaged
C. was damaging D. will damage
By the time I got to the check-out, I realized that I _____ my purse at my office.
A. have left B. had left
C. left D. was leaving
John was so sleepy that he could hardly keep his eyes _____.
A. open B. opened C. to open D. opening
_____ this is your first visit to New York, you’d better learn some of the customs.
A. Unless B. Since C. Although D. Until
Stick to your dreams, _____ they will come true one day.
A. so B. or C. too D. and
