问一道四级英语选择题
问题描述：
问一道四级英语选择题
All the flights( )because of the snowstorm,we had to take the train instead.
A.were canceled B.had been canceled C.having canceled D.having been canceled
答
正确答案是D.1.关键：前后之间用逗号隔开,但是却没有用连词连接.这说明这不是由两个独立句子构成的并列句,而是单个句子.而且逗号前的结构其主语all the flights和句子主语we又不同,所以前面是个独立主格结构,它在句...