51. The Emperor ordered that the wonderful cloth ____for him at once.
A. to be woven B. be woven C. should weave D. would be woven
这道题怎么做？？为什么是B？

52. The government proposes that something ___to get rid of air pollution
A. will be done B. is done C. should D. be done
句子的意思是保证将要怎样。。。。为什么不是A是D？

54.He is very brave. I wish I ____ his courage.
A. had B. have C. had had D. would have

wish不是用将来时的嘛？？？为什么不选D选A啊？

51, order后的宾语从句，应该是should加原形动词构成的虚拟语气，而should又可以省略，那么布与编织之间又是被动的意念，所以答案应该选用 B.
52，这个句子和上面的一样，都是谓语动词（propose）后加should虚拟语气，而且可以省略，所以答案就只能是 D 了。
54，这也是虚拟语气的一种用法。wish动词后的虚拟语气，是通过动词的时态表现出来，现在时或将来时，用过去时态；过去时，用过去完成时态。而“但愿我有他那样的勇气”，也是指现在，而不是将来，所以答案要选 A 了。

看来关于虚拟语气，你还要认真地学习一下。祝学习进步！