The study you have been making ________ the ancient Chinese characters is an instructive job.
We all think Mr. Smith __________ a new house if more new houses __________.
If better use is __________ of your spare time, you'll make great progress in your study.
English is difficult __________ well in a short time.
Paul doesn't have to be made __________. He always works hard.
The careless driver is __________ for the traffic accident that __________ yesterday.