Training astronauts ________ not an easy thing.

My brother brought me a few reference books, but _________ of them was of any use for my report.

Hardly had I got home ___the telephone rang.

So clear was his _________ of the case that others had no more to say.

___________ that Bob had got promoted，his friends came to congratulate him.

By the end of this year Mr. Smith ______ in our company for exactly three years.

l didn＇t answer the phone ______ I didn＇t hear it ring.

When I first arrived in Japan, I was surprised ______the way people greeted each other.

They think that you will go to Bei Hal Library tomorrow, __________ .

It is high time someone __Nick that each member of a team has to do his share of work.

340. He doesn＇t dare to leave the house ________he should be recognized.