十六种：

1. 一般现在时 be / do /does2.一般过去时 was / did3.一般将来时 will do / be4.现在进行时 be doing5.现在完成时 have/has done / been6.现在完成进行时 have/has been doing7.将来进行时 will be doing 8.将来完成时 will have done / been9.将来完成进行时 will have been doing10.过去将来时 would do / be11.过去完成时 had done / been12.过去进行时 was doing13.过去将来完成时 would have done / been14.过去将来进行时 would be doing15.过去完成进行时 had been doing16.过去将来完成进行时 would have been doing