To air pollution, we should walk or take a school bus to school.
We will Class 2 in the final match.
Let's this matter.
What's your ？
This idea seems good, but you need to .
The old man was excited to his son.
the rice when your hands are wet.
Betty, what are your this summer holiday?
I if the report is .
his is very difficult.
Many people became homeless the earthquake.
going to China.
——是的，有。/不，没有。
— any trees beside the lake?
— （肯定）（否定）
the matter?
