he is a student.he had been a student/ he has been a student.中文理解起来有什么不样哪句能看出现在还是不是学生呢?完成时必须后面要有年限才对么?
问题描述：
he is a student.he had been a student/ he has been a student.中文理解起来有什么不样
哪句能看出现在还是不是学生呢?完成时必须后面要有年限才对么?
答