OG11-9新问题

9. Sunspots, vortices of gas associated with strong electromagnetic activity, are visible as dark spots on 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 darkspots although never sighted at

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

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

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 ever beensighted...equator).Sunsports 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 the second.(The adjective visible is a complement and is a parallel to the past participle sighted.)Both parts of the sentence conclude with phrases indicationg 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 distors 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 subjext and sighted is not a complete verb

D.Although usually introduce 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

（做完了大全，重新回到OG，发现还是有很多不明白的地方，汗！还有一个月了，大家帮忙！！！）

不懂，C除了用appear跟原句的be visible不同外，although从句不能看成省略形式吗？

同样的省略在OG11-8“if  not  accompanied  by……”不就成立吗？

另外，这里的as是作什么用的？是visible固定用法，还是作为作“作为”解？否则应该跟句子啊？

最后，想确认一下E的解释，说这里是指代不清，我想确认的是which可以跳跃修饰dark spots吗？还是只能就近修饰surface？

那么and its intended referent,either sunspots or dark spots,becomes unclear是什么意思呢？

我也一直很困惑OG解释的一些说法，刚完成了第一遍OG的总结，就觉得OG在一些地方的解释是自相矛盾的，特别是关于代词指代的问题，经常是不同的题说法不同，看了以前的NN们的讨论，还是一句话，逻辑最大！

C选项看作省略形式我开始也困惑来着，但后来把sunspots are代进去，发现感觉不怎么顺，我想可能是因为后面有个never,好像一般有never应该用完成时态，强调至今为止，还从来没有怎样怎样（这只是个人感觉，还没有查到理论依据）

as应该可以理解成“作为”，即以dark spots的形式被看见

最后那个指代问题，我觉得是最不好解释的，which应该是能够跳跃修饰的，但我想本题是想表达sunspots从来没在赤道和极地发现过，所以最好是直接修饰sunspots (说实话，那句The relative pronoun which should immediately follow its referent才最欠扁，明明很多题目里就是跳跃修饰的）

不知道解释得对不对，请大家指教

有没有人觉得C最大的问题在于the slight diff. between appear and "be visible"?, I think the word "appear" put more meaning on the subject other than the situation "visible", i.e., the situation was seen by the human,not "appeared" itself (On which situation, it might not be seen by human).

What do you think? 

我觉得是不是GMAC不倾向于which跳跃修饰了

which做非限制性定从时一般都是就近指代

但是有些句子由于非限制性定从太长，会把其余部分提前，这样确实造成很多的跳跃修饰。

但是一般来说，就近指代是原则，但不是一成不变的原则。

C的省略还原一下是这样的

Sunspots appear on the surface of the Sun as darkspots although（sunspots） never sighted at the Sun's  poles or equator.

这样的省略缺少be，因为sunspots不会主动的sighted，如果没有be，那么although后面的所谓省略形式就是：名词+分词修饰结构。也是错误的。

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

C. appear on the surface of the Sun as darkspots although never sighted at

E. appear as dark spots on the Sun's surface, which have never been sighted on

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

OG的解释没问题，它并不是否定which可以跳跃修饰这一用法，但在选项E中，which不可能跳跃修饰，因为如果你将which引导的从句理解为主语sunspots的定语，这就是个sentence fragment，即只有一个由which引导的定语从句所修饰的名词，谓语appear被夹在中间，句子结构有问题。

C中省略的部分应该是have been，这样的省略不正确，因为并列谓语只有结构相同时才可以省略相同部分，但在C中前面谓语是主动appear，后面是被动，无法省略。

第8题中的if not accompanied，我将它看作插入语，过去分词做定语。不知道这样行不行？

Rising inventories,
            when unaccompanied correspondingly
            by increases in sales, can lead to production cutbacks that would hamper economic growth.

E. if not accompanied by corresponding increases in sales, can lead

仅供参考。

C中的连词although 不能表示并列吧,为什么不可以看成是状语从句的省略形式阿，可以看成省略了are，为什么一定要看成省略了have been 呢？

请NN们指教！

满足两个条件：

1.主从句两主语相同

2.从句为主系表结构，

那么从句必须是A be B才可以是吗？

也就是说原文中C选项sunspots have never been sighted …不是主系表结构所以不能省略了对吗？