重点讲解：
1. a whiff off 一阵(气味) ；
He caught a whiff of her perfume.
他闻到了她身上的一股香水味-^]!zhmp(K。
2. turn on 启动；开启；
Parents can programme the machine not to turn on at certain times.
父母可以设定这台机器的程序，使它在特定时间段无法开启qBbnzorfLv.%^FEqB)G。
3. be disinterested in 不感兴趣的；不关心的；冷漠的；
Lili had clearly regained her appetite but Doran was disinterested in food.
莉莉显然已经恢复了食欲，但多兰却提不起胃口eXX0i99^6.pvK。
4. be exposed to 使受…的影响；使接触；
We are exposed to an overwhelming number of chemical contaminants every day in our air, water and food.
我们每天都会通过空气、水和食品接触到数量惊人的化学污染物%jsn=qd21|2Qg7-4Ue。