大全19-4 与 OG11答案不一样 对OG的解释有疑问

4.   Sunspots, vortices of gas associated with strong electromagnetic activity, are visible as dark spots on the surface of the Sun but have never been sighted on the Sun’s poles or equator.

(A) are visible as dark spots on the surface of the Sun but have never been sighted on

(B) are visible as dark spots that never have been sighted on the surface of the Sun

(C) appear on the surface of the Sun as dark spots although never sighted at

(D) appear as dark spots on the surface of the Sun, although never having been sighted at（A）

(E) appear as dark spots on the Sun’s surface, which have never been sighted on

OG11th: The correct parallel structure in the original sentence emphasizes the contrast between where sunspots are found (are visible ... Sun) and where they are not (have never been sighted ... equator). Sunspots is the subject of the sentence, are is the verb of the first part of the contrast and have been sighted is the verb of the second. (The adjective visible is a complement and is parallel to the past participle sighted.) Both parts of the sentence concluded with phrases indicating location. The contrast itself is indicated by the conjunction but.

A. CORRECT, this sentence clearly and correctly draws a contrast between where sunspots are found and where they are not.
B. Changing the modifying clause so that that never ... Sun distorts the meaning of the sentence; the contrast is lost
C. Although typically introduces a subordinate clause, which has a subject and a verb, but here there is no subject and sighted is not complete verb.
D. Although ususally introduces a subordinate clause, but there is no subject of the clause and having been sighted is not a complete verb phrase
E. The relative pronoun which should immediately follow its referent; here which illogically follows surface, and its intended referent, either sunspots or dark spots, becomes unclear.

The correct answer is A.

答案是A,没有疑问

我的问题是,C,D中的although引导状语从句,省略主语和谓动词,难道不可以吗?

UP!

有没有路过的NN帮忙看一下呀

有些表示时间、条件、让步、地点以及方法状语从句中，有两种情况可以出现省略现象。
1、谓语包含动词be的某种形式，主语与主句的主语一致，可以将从句的主语及动词be省略。
eg:  The boy will make a lot of trouble when left alone.
2、谓语包含动词be的某种形式，主语为形式主语it，可以将从句的主语及动词be省略。
eg: Try to explain this new theory and give actual examples when necessary.

更多例句：
Look out for cares when (you are) crossing the street.
When (it is) taken according to the directions, the drug has no side effects.
Although (she was) not yet nine months old, she was able to walk without support.
Fill in the blanks as (you are) asked.
If (he is) not invited, he won't go to your birthday party.

我们遇到的很多情况下，连引导词都是省略的。
(Although)Not yet nine months old, she was able to walk without support.

谢谢everann

按照这样说来,把C带入原句:Sunspots, vortices of gas associated with strong electromagnetic activity, appear on the surface of the Sun as dark spots although never sighted at the Sun’s poles or equator.

这个句子应该没有问题呀

但是为什么OG的解释却说:C. Although typically introduces a subordinate clause, which has a subject and a verb, but here there is no subject and sighted is not complete verb.

OG的意思好像是这里主语和谓动不能省.这是为什么呢?

perhaps OG thinks that a subordinate clause without a subject or a verb will lead to misunderstanding. in that case, both "sunsports are never sighted" and "dark spots are never sighted" can be considered acceptable.

前面是n.+ are + adj. 形式，而后面那个sighted算是一个被动式，和adj.不并列，没有办法共享are吧。