重点讲解：
1. clean up 清理，清除（污染物）；
例句：We should clean up the dirty parts of the sea.
我们应该清除海里的污染部分19o|@1o@g*7。
2. a clean bill of health 身体状况良好；
例句：President Mitterrand, 75, has been given a clean bill of health by doctors in Paris.
巴黎的医生们告诉75岁的密特朗总统，他的身体非常健康q&jE;q%Lr2w*Hxt.vT-。
3. take the lead 领先， 带头；
例句：They took the lead in conducting the experiments.
他们带头做试验0J4qwDI2rT~O&a;70r。
4. thanks to 幸亏；归因于；
例句：Thanks to that job I became an avid reader.
多亏了那份工作我才成了一个喜欢阅读的人ID|1~u(4j^&ieaXlo9。
5. benefit from 获益；对…有益；有利于；
例句：A stammering child can benefit from speech therapy.
口吃的孩子可以从言语矫治中获益m(C.C)2Y*&-+p_-si1RN。
6. be attributable to 可归因于…的，可归结于…的；
例句：10,000 deaths a year from chronic lung disease are attributable to smoking.
吸烟导致每年有1万人死于慢性肺病K(NAK5)AP+CeGik9cMU9。
7. grapple with 努力解决（问题）；设法克服（困难）；
例句：The economy is just one of several critical problems the country is grappling with.
经济问题只是该国正竭力解决的几个关键问题之一)|1hyl6&=iGZA。
8. lag behind 落后；赶不上；
例句：The restructuring of the pattern of consumption in Britain also lagged behind.
在消费结构重组方面，英国也落后于人Q3@HmLnbKk9bZE。