We apologize for any inconvenience you _______ have been caused by the delay of the flight.
A. may B. would C. must D. need
The police say there is a $50,000 _______ for any information that helps them find the killer.
A. income B. fee C. bill D. reward
Most whales must come up for air after several minutes, _______ a few can stay under water for an hour or more.
A. while B. or C. for D. so
The numbers that researchers get from the experiments can be _______, just like number puzzles.
A. disappointing B. inspiring C. worrying D. confusing
_______ the house is empty, memories flood my mind of a time when it was filled with life.
A. Since B. Unless C. As if D. Even though
By the time a child is five, he _______ hundreds of hours of television.
A. will watch B. will have watched C. had watched D. is watching
