问题

In my opinion, the key ____air pollution is to inspire people to take public transport in big cities.

A:reduced
B:reducing
C:to reduce
D:to reducing

正确答案是：

同类题型

I realized strength and courage aren’t always ________ in medals and victories, but in the efforts we make.

I am sorry, but I didn’t mean to keep you waiting here so long. Can you ________ me

_______ in the regulations that you should not tell other people the password of your e-mail account.

Sally shouted with joy when she knew she won the first.

I think beef noodles is ________ of all.I like it very much.