You'd better not keep the door open中为什么open不用加ing?

You'd better not keep the door open中为什么open不用加ing? Please open the door,will you?为什么不用wll not look,the door is open,为什么open不加ing? you'd better keep the windows ----open 改错：You had better not to open the door. Do you mind opening the door.为什么open要加ing don‘t keep the door open 还是keep not the door open,keep什么时候作系 keep the door close/open? 英语语法填空You'd better have the windows ＿(open) and the door＿(cl （ ）you( )(keep)the door open when you go out You'd better _ The window open 请问：the oceans were open to sail中open为什么不加ing?