---Mr. White didn’t come last night, did he? ---No. We for him. A whole night was wasted. A. had waited B. have been waiting C. were waiting D, had been waiting
We have very strict quality control and anything imperfect is ____, so customers feel secure about our products.
Before you____the design of this product, you need to study the market carefully.
Our government is trying its best to ____the social security system to protect people’s rights.
Although the painting is very ____ pleasant, it is thought to be copied with a modern printing machine.
The spokesman said that this was a(n)____negotiation (谈判) because it solved a lot of problems between the two sides.