Lesson four is _most difficult lesson,but it isn't _most difficult lesson in Book2.答案是the;the不小心打错了。不排除答案是错的可能。

问题描述:

Lesson four is _most difficult lesson,but it isn't _most difficult lesson in Book2.答案是the;the
不小心打错了。不排除答案是错的可能。

*,在没有其他定语修饰时,一定要加the
a,the 我也认为不对!