These three teachers vary_____their manners of teaching.

When he really does something wrong, he is willing to （ ）.

I have no objection （ ） your design for the new type of machine this time.

The wind_____us and we won the sailing race.

_____at the door before you enter the room, please.

It doesn’t matter _____ you pay in cash or by credit card in this store.

Our main concern is to _____ the living standard of the people.

If you suspect that illness might be serious，you should not （ ） going to the doctor.

Plastics is a kind of （ ） which is widely used in industry.

We decided to move to a quiet place, for we couldn’t （ ） the noisy environment here any more.

The factory, including its machines and buildings, （ ） burnt last night.

（ ） his last word, he got into a taxi and disappeared in no time.