（ ）I failed in English a third time,I had no doubt about my gift for foreign languages.
问题描述：
（ ）I failed in English a third time,I had no doubt about my gift for foreign languages.
A.By the time B.Until C.After D.Unless
正确答案是B,为什么不是D,unless=if not
答
简单点就是：
unless是除非的意思,这是一种假设,是还未发生的,所以句子中须有将来时,
例如：除非我病了,我才不来.
Unless i am ill,i will come.
=If i am not ill,i will come .
而题目句子当中用的都是过去时态,所以不选它