—Look! What a nice classroom! — Yes, it ________ every day.A. is cleaning B. has cleaned C. is cleaned
Our city has a _____ population .
Sichuan is famous _____ its hot(辣的) food.
I don’t like swimming, ______ I won’t join the swimming club.
It’s important ____the piano well.
The _____you work , the _____grades you will get.