大全601，还有疑问没弄懂

24.   Recently implemented “shift-work equations” based on studies of the human sleep cycle have reduced sickness, sleeping on the job, fatigue among shift workers, and have raised production efficiency in various industries.

(A) fatigue among shift workers, and have raised

(B) fatigue among shift workers, and raised

(C) and fatigue among shift workers while raising

(D) lowered fatigue among shift workers, and raised（C）

(E) and fatigue among shift workers was lowered while raising

这里C答案while之前的平行结构我没有问题，我的疑惑在于，为什么while之后要用raising，while 不是平行了两个动作have reduced和raising吗？

请NN们指点迷津！

while 是同时的意思，我把raising看成have reduced 的结果了，作伴随的现在分词了

你一问我也有点糊涂了

多问一句：sleeping是sickness的同位语，修饰sickness的吗

do sth while doing sth在GMAT中很常见，可以当个固定搭配。

sleeping不是sickness的同位语

[have reduced sickness, sleeping on the job, and fatigue among shift workers ]while raising，[]中sth,sth,and sth这种形式在GMAT特别常见，就是3个并列，最后一个comma后必加and。

谢谢，原来sleeping可以做名词用啊

学艺不精，多谢

是的，这种结构是出现过几次。

多谢yukon，祝复习愉快！

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