1. brevity 短暂；简洁

He is famous for the brevity of his speeches.
他以言词简洁着称.

2. drowse vi. 打瞌睡

He drowsed in the sun.
他在阳光下打瞌睡。

3. capricious adj. 无定见的，变幻莫测的

We can't go camping while the weather is so capricious.
天气如此变化莫测，我们无法去野营了。

4. catalyst n. 促进因素

The action of a catalyst, especially an increase in the rate of a chemical reaction.
催化作用催化剂的作用，尤指加快化学反应速度的

5. catastrophe n. 灾祸，灾难

The flood was a major catastrophe.
洪水是一场大灾难。