8. The solar system is a small part of our        (星系) .

7. Each student in the class is able to        (交流) with foreigners.

 6. Nothing is        (不可能的) if you try your best.

 5. I know the          (宇宙) is timeless and boundless.

 4. Which      (小组) can do it faster?

 3. The sun is at the heart of the solar system and 8      (行星) go around the sun.

2. The     (环境) of the small city is very good，so more and more people like to live there.

1.      (没有一个) of the students has been to Australia.

5.在宇宙中       

6.遥远       

7.绕……转       

8.和我们交流       

1. 在地球上       

2.他们中没有一个       

3.太阳系       

4.成百上千的