一般现在时L'm a student. l'm not a student Are you a student?
一般将来时l'll be a student. l won't do it. Will you go with me?
一般过去时l was a student. l was not a student.Were you at home two hours ago?
现在进行时 l'm typing. l'm not typing.Are you typing?
现在完成时l've done it.l've not done it.Have you done it?
过去进行时l was sleeping while he telephoned me.l was not sleeping while he telephoned me.Were you sleeping while he telephoned you.必须是一个时间点
过去完成时l had done it before he called me.l had not done it before he called me.Had you done it before he called me?