请教一道大全！

frey83

cyt1111111 发表于 2015-6-12 16:11
那698的E为什么不对呢

前面打错了，是ed没有说明动作发出的人

cyt1111111

frey83 发表于 2015-6-12 16:19
前面打错了，是ed没有说明动作发出的人

麻烦看看这道题：The debate over bilingualeducation centers on the issue of whether the United States should foster theidea of single common language, an idea, some believe, that has in the past beencrucial in binding diverse constituencies together.
(A) been crucialin binding diverse constituencies together
(B) been crucialas a binding together of diverse constituencies
(C) been crucialto bind together constituencies that are diverse
(D) become crucialin binding together diverse constituencies（A）
(E) become crucialto bind together constituencies that are diverse
为什么不选D

frey83

cyt1111111 发表于 2015-6-12 16:41
麻烦看看这道题：The debate over bilingualeducation centers on the issue of whether the United Stat ...

an idea... that ( ) in the past
in the past表示在过去一直是这样，所以用be而不用become

cyt1111111

frey83 发表于 2015-6-12 16:46
an idea... that ( ) in the past
in the past表示在过去一直是这样，所以用be而不用become ...

好的，谢谢！