题目内容：

 

1.中国已经成功地举办了2008年奥运会。

China has already _______  in  _______ the 2008 Olympic Games.

2.我们应该执行独生子女政策来控制人口。

We should  _______  _______ the one-child policy to control the population.

3.每年成百上千万的游客到中国来参观长城。

Every year  ______ ______ visitors come to visit the Great Wall.

4.自从我来到了马坪中心中学我就买了这辆自行车了。

We_______  _______ the bike since I came to MaPing Center Middle School.

5.因为空气污染，我都呼吸困难了。

It’s _______ for me to _______ because of the air pollution.