Why not ___(ask) him to come from?

Why not ___(ask) him to come from? why not ask the man over there?改为同义句 why ___ ___ask the man over there? Why not ()(teach) him English Why not()(ask)your father for help? why not ask your friend______some advice? why can not i ask question? Do not ask people why ,ask yourself what. why don't you go and ask him for help? Why not express your love to him? why not call him tom for short Why not buy sweeter to give him? i have lots of question _.why not ask him?he is the only person_the answers.为什么第二个空填to know呢? ( ) Why not ____ your teacher for help when you can’t finish ___ it by yourself 选哪个 为什么A.ask;write B.to ask;writingC.ask;writing D.asking;write Why don't you ___(ask)Mr Smith for help --to joe’s wedding ,I gave him a call to ask why.A Having been not invited B Being not invited CC Not inviting D Not having been invited I must ask him to give up smoking.改为同义句：I must ask him to ___ ___. Yes,she won the first ___ in the singing competition when she was young.还有一道：Why not ask her to ____ in THE VOICE OF CHINA? 英语句式结构解析askI ask him why.这里是ask的双宾结构吗?可以用why?那我能不能说ask him the reason?