couldn't 和 shouldn't4.He__ the 8:20 bus because he didn't leave home till 8:25.A couldn't have caught B ought to have caught C shouldn't have caught D must not have caught为什么选C,A哪里不妥,谢谢!问题补充：那为什么 She must be in the dormitory now. No, she __ be there. I saw her in the classroom a minute ago.A mustn't B can't C couldn't D wouldn't可以选B呢?是不是如果有shouldn't的话答案就是shouldn't了呢?
问题描述：
couldn't 和 shouldn't
4.He__ the 8:20 bus because he didn't leave home till 8:25.
A couldn't have caught B ought to have caught C shouldn't have caught D must not have caught
为什么选C,A哪里不妥,谢谢!
问题补充：那为什么
She must be in the dormitory now.
No, she __ be there. I saw her in the classroom a minute ago.
A mustn't B can't C couldn't D wouldn't可以选B呢?是不是如果有shouldn't的话答案就是shouldn't了呢?
答
问题补充的那个考的是可能性的问题
must太绝对
问题的 shouldn't have caught 在这里有委婉责备的特定用法,更符合情景