中国营养学会推荐乳母应每日额外增加蛋白质（）克。

A.10

B.20

C.30

D.40

根据中文提示填空。

1．He is a very _____________ (勇敢) young man.

2．It is ______________ (危险) to play football on the road.

3．The boy _______________ (倒) the water over a dog. The dog ran away.

4．He has a lot of _______________ (麻烦) with his homework?

5．I am taller and _______________ (苗条的) than David.