2. Elephants are the most e______ animals on the land.

1. We can protect the e______ by planting more trees.

5. Printing was developed greatly and books could be produced more quick and cheap.　

　　　　　　　　　　　　　　　　　 ___________

4. The first printing books were made by putting ink on a wooden block and holding the paper against it.　　　　　　　　　　　　　　　　 　　

　　　　　　　　　　　　　　　　　 ___________

3. A few people learned to read because the books were expensive and rare at that time.

　　　　　　　　　　　　　　　　　 ___________

2. A new oil field(油田) was invented three days later.　

　　　　　　　　　　　　　　　　　 ___________

1. Paper can be made of silk, cotton, bamboo and wood.

　　　　　　　　　　　　　　　　　 ___________

8. 这个农场种植各种各样的作物，比如小麦、稻谷和棉花。

The farm grows different kinds of crops, _______ _______ wheat, rice and cotton.

7. 他们都买了双程票，以便能节约一些钱。

They all bought round-trip tickets _______ _______ they could save some money.

6. 大明今天早上起晚了，结果误了校车。

Daming got up late this morning. _______ _______ _______, he missed the school bus.