b.Try to find a sentence that can be replaced by the following one:

　 Now it's their turn to be the most important animals on the planet

c.Translate the following sentence.

1.It was not immediately obvious that water was to be fundamental to the development of life.

2. That made it possible for life to begin to develop.

Vii,Key words

Ⅰ.explode

1). vt.vi（使某物）炸开，爆炸 ；炸弹，火药）爆炸

2). （指感情）激发 +with anger 勃然大怒

3). （指人口）突然或迅速增加

翻译iThe firework exploded in his hand and he was hurt seriously.

iiI was frightened when she exploded into loud laughter.

iiiNow it is not easy to find jobs with the exploding population.

explosion n. 爆炸（声）

explosive adj.爆炸性的，易爆炸的 n.炸药，爆炸物

Ⅱcool adj.凉快；冷静；冷淡