It is reported that in our country cities __________ heavy air pollution that is 30 percent above the national standard or higher should try to meet standards by 2030.
There was a terrible noise _____ the sudden burst of light.
Do you consider _____ any good doing many scientific experiments?
When he failed to beat John, he felt he had _____ his friends.
— Was Andrew there when you arrived? .— .Yes, but he _____ home soon afterwards.
I really don’t understand _____ her like that.