词形变化。

1.Don't spend too much time           (sit)in front of the computer.

2.Our favourite festival is            (child)Day.

3.How many baskerball              (play)are there in a match?

4.Mike goes swimming              (one) a week.

5.Tom,             (not be) late for school again.

6.Mike with his parents           (watch) TV in the evening.

7.Let Tom              (fly) kites after school.

8.The boy             (call) Jim is her son.

9.Please get me some             (information) about the Great Wall.

10.Our English teacher is             (help) to us.

我国列入原冶金部标准的低合金高强度钢共有21种，它们是按（）高低来分类的。共有（）MPa、（）MPa、（）MPa、（）MPa和（）MPa和（）Mpa六个级别。