It's necessary for us to improve our environment. [ ]

A. become better

B. make something bad

C. help

D. make better

根据汉语，完成句子。

1．大明想要环游世界。

  Daming wants                                    the world.

2．你父母晚上让你出去吗？

    Do your parents let you                          in the evening?

3．这个周六我打算骑自行车去看我的爷爷。

  I am going to                          to see my grandpa this Saturday.

4．我们有一个新的英语老师。

We have                                                      ．

5．男孩们正玩得高兴。

The boys                                         ．