标题: prep07第二套 第一题 各位帮我区别下B和C [打印本页] 作者: JackCai_WUDI 时间: 2016-9-26 16:56 标题: prep07第二套 第一题 各位帮我区别下B和C 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