16種,常用9種
常用的：
一般現(xiàn)在時(shí) do/does
一般過(guò)去時(shí) did
一般將來(lái)時(shí) will do/be going to do...
過(guò)去將來(lái)時(shí) would/shoud do
現(xiàn)在進(jìn)行時(shí) be doing
過(guò)去進(jìn)行時(shí) was/were doing
現(xiàn)在完成時(shí) have/has done
過(guò)去完成時(shí) had done
現(xiàn)在完成進(jìn)行時(shí) have/has been doing
不常用的：
將來(lái)進(jìn)行時(shí) will/shall be doing
過(guò)去將來(lái)進(jìn)行時(shí) would/should be doing
將來(lái)完成時(shí) will/shall have done
過(guò)去將來(lái)完成時(shí) would/should have done
過(guò)去完成進(jìn)行時(shí) had been doing
將來(lái)完成進(jìn)行時(shí) will/shall have been doing
過(guò)去將來(lái)完成進(jìn)行時(shí) would/should bave been doing