一般现在时 do; am/is/are
现在进行时 am/is/are + doing
现在完成时 have/has+ (been) done
现在完成进行时 have/has been doing
一般过去时 did; was/were
过去进行时 was/were+doing
过去完成时 had+done
过去完成进行时 had been doing
一般现在时 do; am/is/are
现在进行时 am/is/are + doing
现在完成时 have/has+ (been) done
现在完成进行时 have/has been doing
一般过去时 did; was/were
过去进行时 was/were+doing
过去完成时 had+done
过去完成进行时 had been doing