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 become 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
沒有人問這題
雖然選對了答案 可是不懂PREP筆記里說的
there have been錯誤
是什麼意思?
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