问题描述：
I know that it must be my father.过去式应该是...
I knew that it must have been my father.
I knew that it must be my father.
哪个对?
我一直都认为第一句must have been 是对的
但昨天我看见一句
She knew that it must be the baker.
I knew that it must have been my father.
I knew that it must be my father.
哪个对?
我一直都认为第一句must have been 是对的
但昨天我看见一句
She knew that it must be the baker.
问题解答：
我来补答展开全文阅读