求助，OG107，看了之前的帖子依旧不明白。。。

fightingxuxu

107. While it costs about the same to run nuclear plants as other types of power plants, it is the fixed costs that stem from building nuclear plants that makes it more expensive for them to generate electricity. (A) While it costs about the same to run nuclear plants as other types of power plants, it is the fixed costs that stem from building nuclear plants that makes it more expensive for them to generate electricity. (B) While the cost of running nuclear plants is about the same as for other types of power plants, the fixed costs that stem from building nuclear plants make the electricity they generate more expensive. (C) Even though it costs about the same to run nuclear plants as for other types of power plants, it is the fixed costs that stem from building nuclear plants that makes the electricity they generate more expensive. (D) It costs about the same to run nuclear plants as for other types of power plants, whereas the electricity they generate is more expensive, stemmingfrom the fixed costs of building nuclear plants. (E) The cost of running nuclear plants is about the same as other types of power plants, but the electricity they generate is made more expensive because of the fixed costs stemming from building nuclear plants.

正确答案为B

问题：关于E选项，OG解释中写道：The preposition for is necessary in the comparison of the costs. 看了前面的帖子依旧不明白为什么for是必须的。。写上我的理解，求指正！我的理解：E选项中：The cost of running nuclear plant和other types of power plants平行的原因在于后者省略了the cost of running,即补全后的平行为The cost of running nuclear plant和 （the cost of running ）other types of power plants。这么想为什么不对？求指正，谢谢！

fightingxuxu

求助求助

fightingxuxu

自己顶下~

fightingxuxu

木有人啊

fightingxuxu

不要沉啊，求解求解

wczwcz

我觉得as后省略的是the cost而不是the cost of the running，所以要加上for

orientalradio

你说得对，这里是比较The cost of running nuclear plant和 （the cost of running ）other types of power plants。
简化为A of B is the same as C, 尽管意思上没有问题， 但在语法上，C是和主语A比较，还是和介词短语限定的A of B比较，不明确。 如果选项E是about the same as OF other types of power plants，我想你一定不会有疑问。但这个题的可恨之处在与他用了一个意思相近别的介词短语A  for B 来代替 A of B.
不知道解释清楚没有？

JaeYoong

因为介词短语补出的时候你才知道是省略了介词短语的名词，而没有介词结构造成是跟主语比较的感觉

fightingxuxu

orientalradio 发表于 2013-8-12 23:21
你说得对，这里是比较The cost of running nuclear plant和 （the cost of running ）other types of power ...

感谢解答~我理解了一下，是不是这个意思：若不补出介词for，会造成other types of power plants 到底是和costs（即你说的A）比较还是和running nuclear plant（即B）比较的歧义，所以为了明确比较对象，必须要加上介词才行~

qiongle

for要有是因为，少了for就缺失了比较对象，从而比较不对等，句子逻辑意义就错了。少了for不就变成the cost of running nuclear plants和 other types of power plants对比了么？从句意理解一下吧。