93. If you can speak very ______ English, you will have more chances to find a job than others.

It was about 600 years ago ______the first clock with a face and an hour hand was made .

Yang Liwei was a student at this flight school from 1983 to 1987, he studied very hard and was made chairman of the Students’ Union.

We should keep the classroom and tidy.

It is _____ to feel tired after such a long trip.