动词填空。

1.Would you please give me some advice on ________ (swim)?

2.I’d like to, but I have something ________ (wash) today.

3.Nothing ________ (be) difficult if we put our heart into it.

4. ________ (not be) late for school.

5.Just now, Mr. Smith ________ (invite) us to join the skiing competition.

6.Don’t make any noise, Grandma ________ (sleep).

7.I’ll wait here for your mother until she ________ (return) from work.

8.The monkey ________ (hide) themselves under the trees when it was rainy.

9.He with his friends usually ________ (play) football after school.

10.What are yon going to do? How about ________ (go) out to play football?

什么是八分？八分书在哪个时期普及？