---- An ant has two stomachs --- one for itself and the other for others.
----Really? Quite interesting. I anything about it.
A. don’t know
B. hadn’t known
C. haven’t known
D. didn’t know
网友回答
A. don’t know
B. hadn’t known
C. haven’t known
(答案→)D. didn’t know
解析：考查时态。“蚂蚁有两个胃，一个自己用一个为别的蚂蚁。”“真的么？我不知道。”在对话时不知道，所以用一般过去时态。