Each year companies in the United States could save as much as $58 billion annually by preventing illness among employees and gain as much as $200 billion through improving performance of workers if they simply provided offices with cleaner air.

　　(A) annually by preventing illness among employees and gain as much as $200 billion through improving performance of workers if they simply provided

　　(B) annually if they prevented employee illness and gain as much as $200 billion through worker performance improved by simply providing

　　(C) annually in employee illness prevention and gain as much as $200 billion through worker performance improved by simply providing

　　(D) in employee illness prevention and gain as much as $200 billion through improving performance of workers if they simply provided

　　(E) by preventing illness among employees and gain as much as $200 billion through improved worker performance if they simply provided

原文意思：

　　每年美国的公司能通过预防员工生病节省一部分钱并且能通过提高员工战斗力挣一些钱。

题目分析：

　　读完 A 语义说的通，留着。

　　B 用 they，可是 prevent 和前面的动词发起者没有变化，不用加 they，干掉。C 读到 in employee illness preventing 就很别扭，语义没有 A 通顺，干掉。

　　D 和 C 犯了相同错误，干掉。

　　E 乍一读也没有明显错误，我们把这个选项和 A 进行对比，一个用 imporving 另一个用improved，而 performance 是被 improved 的，所以 E 语义更合适，我上课反复强调，我们上来争取杀四个，如果做不到，留下来的选项如果长的比较像还是可以理解的，就像这道题的 A 和 E 一样，没有仔细看得情况下把 A 留下是可以理解的!