题目内容：

6.he looks as if he ______ nothing about the news
A)would know
B)knew
C)would have known
D)should know

优质解答

would know将会知道,would have known过去将来完成时（表示在过去某一时间对将来某一时刻以前所会发生的动作）,should know应该知道
他看起来好像对消息毫不知情,其余三个选项都是对将来的预测,不符合句意