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