根据中文或英语解释写出形式正确的单词。

1.These papers must be _________ (写) in English at once.

2.Marco Polo was a famous _________ (a person who likes travelling).

3.These _________ (the people from Japan) are having a good time in England.

4.The leaves _________ (another way of saying turn) green in spring.

5.Don't _________ (犯) the mistakes in your exercise.

6.Shall we go _________ ( 买东西) next Monday morning?

7.They often went to work on ________ (步行) when they were young.

8.He wants to _________ (get something from a shop with money) a present for his mother.

9.I have seen the ________ (people who look after the sick people) already.

10.Mr Wang and Miss Green will be _________ (回来) soon.

全球变暖的原因被认为是温室气体的排放，下列哪个气体不是引起温室效应的物质（）.

A.氩气

B.二氧化碳

C.氟利昂

D.甲烷