问题描述：
I should have gone with them,but I ___ my homework in time 一道英语语法题
为什么答案是could not finish
而不是could not have finished 或 might not have finished 或might not finish
为什么答案是could not finish
而不是could not have finished 或 might not have finished 或might not finish
问题解答：
我来补答展开全文阅读