词汇讲解：
1. constant adj. 不停的,接连不断的,持续的
例句：He hates his wife's constant nagging.
他讨厌他妻子唠叨不休。
2. consumption n. 消费, 消耗; 消费[耗]量
例句：Consumption of oil has declined in recent years.
石油消耗量在最近几年下降了。
3. outgrow vt. 生长或进步超过了…
例句：She outgrew the company she worked for and found a better job somewhere else.
她进步很快, 不再满足于她所在工作的公司, 于是又在别处找到一份更好的工作。
