由OG205所想到的

205. The peaks of a mountain range, acting like rocks in a streambed, produce ripples（波纹） in the air flowing over them; the resulting flow pattern, with crests and troughs that remain stationary although the air that forms them is moving rapidly, are known as "standing waves."

(A)  crests and troughs that remain stationary although the air that forms them is moving rapidly, are

(B)  crests and troughs that remain stationary although they are formed by rapidly moving air, are

(C)  crests and troughs that remain stationary although the air that forms them is moving rapidly, is

(D)  stationary crests and troughs although the air that forms them is moving rapidly, are

(E)   stationary crests and troughs although they are formed by rapidly moving air, is

The main challenge in this sentence is to observe the agree­ment of subject and verb (the resulting flow pattern... is known...) despite the distraction of a complex intervening structure containing several plural elements (with crests and troughs...). Choices A, B, and D can, therefore, be eliminated because they use an incorrect plural verb form, are. Choice E uses the correct verb form, is, but it incorrectly introduces a dependent adverbial although clause into a prepositional phrase (with crests ...). Choice D also makes this error. Such dependent clauses can only occur in the predicates of full clauses. C, the best choice, uses the correct verb form, is, and correctly puts the although clause inside the predicate of the relative clause (that... rapidly).

介词短语中用了一个从句错，although这样的从句只能用在有主句的句子中-必须有主句谓语动词。

sth that remains plus a.这种形式的定语从句是不能简化的;系动词的话就可以简化，注意这个简洁的陷阱。

类似sth that remans + adj.形式的而不能简化的从句还有嘛?

remain, become, come, go 作为一个动态的过程, 不可以省略或者改成be的形式

OG77.   Though the term “graphic design” may suggest laying out corporate brochures and annual reports, they have come to signify widely ranging work, from package designs and company logotypes to signs, book jackets, computer graphics, and film titles.

(A) suggest laying out corporate brochures and annual reports, they have come to signify widely ranging

(B) suggest laying out corporate brochures and annual reports, it has come to signify a wide range of

(C) suggest corporate brochure and annual report layout, it has signified widely ranging

(D) have suggested corporate brochure and annual report layout, it has signified a wide range of（B）

(E) have suggested laying out corporate brochures and annual reports, they have come to signify widely ranging

OG223. As business grows more complex, students majoring in specialized areas like those of finance and marketing have been becoming increasingly successful in the job market.

(A) majoring in specialized areas like those of finance and marketing have been becoming increasingly

(B) who major in such specialized areas as finance and marketing are becoming more and more

(C) who majored in specialized areas such as those of finance and marketing are being increasingly

(D) who major in specialized areas like those of finance and marketing have been becoming more and more（B）

(E) having majored in such specialized areas as finance and marketing are being increasingly