1.   

Since the start of the space age, more and more littering has occurred in orbits near Earth, often because the intentional discarding of lens caps, packing material, fuel tanks, and payload covers.

(A) more and more littering has occurred in orbits near Earth, often because

(B) orbits near Earth have become more and more littered, often from

(C) orbits near Earth became littered more and more, often resulting from

(D) there have been more and more littering of orbits near Earth, often because of

(E) there had been littering more and more of orbits near Earth, often with

OA is B

请问 B里面的 often from到底是谁的modifier? 我找不到可以被他修饰的Noun啊.

如果 说often from是做adverbial modifier，它修饰的动词是哪一个？ 这算是那一种结构have become...., from...?

应该是B吧...

often from sth. sth. and sth 介词短语作伴随状语 修饰动词become

但是从since 开始 决定了动词时态一定时限在完成时， 所以就可以派出C E

A 中because后面是名词并列 不是主位结构 排除A

D 中there be + 动名词结构在GMAT里面是不接受的 排除D

也就只剩下B可以选了

 from…介词短语作方式状语

Do you speak from experience?

你是就经验而谈吗？