GWD29-41

Gas hydrates, chemical compounds of water and natural gas, are increasingly being studied for their potential to be huge reservoirs of energy, possibly causing sea floor instability, and significant contributors to global warming.

1. to be huge reservoirs of energy, possibly causing sea floor instability, and
2. to be huge reservoirs of energy, possibly causing sea floor instability, and even as
3. as huge reservoirs of energy, possibly causing sea floor instability, and
4. as huge reservoirs of energy, and the possible cause of sea floor instability,
5. as huge reservoirs of energy, as possible causes of sea floor instability, and even as

answer is A

My answer is E, free for discussion.

I prefer A.

E has 3 problems.

1) Unlike “potential to” in A, “potential as” in E is unidiomatic. provides capital and guidance to minority businesses that have potential to become future suppliers or customers of the sponsoring company. each cell has the potential to develop in a variety of different ways (both sentences are taken from OG)

2) “even”, as an adv., cannot modify “potential”, which is a noun, or "as", which is a prep. Although “even” can be used as an adj, but it means “level”, which is not appropriate in this sentence.

3) Original sentence doesn’t have “even”. An extra “even” indicates that “contributors to global warming” is more audacious than the other 2, changing slightly the meaning of the original.

A is not a perfect answer either, since “possibly causing” is ambiguous. But present participle in the middle of the sentence usually modifies the preceding noun, and, in this case, the noun is “reservoir”.

开始觉得选e，不过仔细看看还是a，

如果选e的话，reservoirs，与 cause, contributor不是同义词，应该是把potential作为与后两者平行的还差不多

我选a的理由是，possibly causing sea floor instability并不是与前后两者并列的成分，而是作为修饰potential的作用，大家看看是不是可以这样理解

我认为应该选E,选A的话逻辑意思就不正确了.

A中的possibly causing这样的结构应该是修饰前面整个句子的,即Gas hydrates are increasingly being studied for ....这个事情causeing sea floor instability,这样就不正确了,具体关于这种ing修饰的例子可见大全

再看E,as, as ,even as是很平行的结构,但是偶认为E中有一个小错误,既potential和possible causes之间会有redundancy,个人认为应该把possbile给去掉,不知道大家怎么看?