1. Insects and amphibians appeared. 2. Dinosaurs appeared.

3. The earth became a solid ball. 4.Small plants grew on the water.

5. Reptiles appeared. 6. Plants began to grow on dry land.

7. The earth was a cloud of dust 8. Water appeared on the earth

9. Shellfish and other fish appeared. 10. The universe began with a "Big Bang".

11. Clever animals with hands and feet appeared 12. Mammals appeared.

IV.What's the writing style of the text?

A. Narrative 记叙文

B. Explanation 说明文

C. Essay 散文

v. Phrases and Useful Expressions

1. circle around

2. according to...

a widely accepted theory