一、单项选择（共15小题；共15分）
1. They were all very tired, but of them took a rest.
A. none B. all C. both D. either
2. --- I can't stop smoking, doctor.
--- For your health, I'm afraid you .
A. may B. can C. must D. need
3. --- Hello, may I speak to Mr. Li?
--- Oh, sorry! He to Hong Kong. He will come back in three days.
A. has been B. has gone C. went D. goes
