Students ________________slippers(拖鞋) when they are at school.
— How do you improve your writing skills? —_________ .
I have spent______ on this job. I think I can finish it______this afternoon.
Boy, didn’t you see people were waiting in line? Don’t______in!
The weather is bad. You shouldn’t risk _______ mountains.
------Have you read the______ of the country you are going to? ------Yes. Now I know it’s a country famous for natural beauty.