haven的精选

时间和动作的种类1.一般现在时(do/does)2.一般过去时(did)3.一般将来时(will/shalldo),(begoingtodo)4.一般过去将来时(would/shoulddo),(was/weregoingtodo)5.现在进行时(bedoing)6.过去进行时(was/weredoing)7.将来...