6-10 B C C D A
11-15 A A C A D
16-20 C C D C C
6.根据本人语感 mistakes
7 award 强调奖励 符和题意
8.D(contribute..to..归功于)
9.D(attribute...to...归因于)
10.owe to 归功于
11.A (用whatever 引导主语从句) 12.修饰人数用amount,修饰时间用number
13.accept表接受 与fact搭配表示接受事实,其他各项均不符合题意
14.look forward to是固定搭配,表希望得到的,The holiday we have been looking forward to作为一个整体,作主语,谓语用三单形式,因此选has come.
15.倒装句.正常的语序是 his sister who dressed in black sies by the desk looks like my aunt.
16.which引导状语从句
17.whether引导主语从句
18.if条件句,主句用一般时态,从句用将来时.反之亦然.
19 whichever引导状语从句,表选择
20.however等于no matter how.根据语序,只有C项符合
希望能对楼主有用 我确信正确率应该还是比较高的