B
强调句,如果你把强调的部分去掉,还是可以成为一句句子.那就说明它是强调句...
I didn't realize who he was until he took off his dark glasses.
直到他摘下黑色墨镜我才意识到他是谁.
这种句型以后题目中会出现很多次.读读熟就好..