求问though/although用法嘤嘤嘤

阿影glory

although和though后面我知道应该是引导从句的，但是我记得也看到过可以加分词的用法，
但是刚看了一道题
14. 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
(E) appear as dark spots on the Sun's surface, which have never been sighted on
里面的C选项是因为although后面不能加分词被排除掉的。。（还是其实是因为后面at这个介词用的不对才排掉的？）

所以求问各位NN，GMAT里面到底though、although、if、while这种引导状语从句的词后面可以加分词嘛！！QAQ蟹蟹！

Jagabee

Although在句首的时候, 可以后面跟
a. adj
b. prep phase
c. clause

Although在句中或句尾的时候, 必须跟完整的句子. 但是完整的句子是容许省略的，只要符合状语从句省略的条件
a. 动作主体与修饰的动词的动作主体一致
b. 动词为系动词be

C错误的原因是因为although后面跟的不是一个完整的句子, 而是一个run-on sentence.

if，while引领状语从句, 同样要引领独立的句子, 你看到的分词是省略的结果.

上官雨沫

Jagabee 发表于 2016-11-11 17:06
Although在句首的时候, 可以后面跟
a. adj
b. prep phase

同意！