重点讲解：
1. aim to do sth. 致力于；旨在；以…为目标；
例句：They aim to clear every dealer from the street.
他们打算把街上所有的毒品贩子都清走。
2. as well as 除…之外；也；还；
例句：He wants power as well as money.
他既要金钱也要权势。
3. in addition 另外；加之；除…之外；
例句：In addition, the respondent disclosed professional confidences to one of the patients.
另外，被告还向其中一位病人透露了行业机密。
4. account for （数量或比例上）占；
例句：Together they account for less than five per cent of the population.
他们总共占不到总人口的5%。
5. be prone to 有（不好的）倾向的；易于…的；很可能…的；
例句：He is prone to lose temper whenever disagreed with.
人们和他持有不同意见时，他容易发火。
6. be exposed to 使暴露于（险境）；使遭受（危险或不快）；
例句：The child has been exposed to scarlet fever.
这个孩子曾与猩红热接触过
