two hours' 为什么不是hour's?

two hours' 为什么不是hour's? A two hour B two hour‘s C two hours's D two hours two hours'fishing 可不可以写成 two-hour's fishing about__drive A two-hour B two hours' 选哪个为什么 Two hours' ///////// A two-hour It is about two ( ) drive A.hours B.hours' C.hour's D.hour in an hour's time 和in two hours‘ time another two hours的hour要加s吗 简单英语问题It's two hours' walk.=It's a two-hour walk.为什么前面的不要加a, It's two hours' drive和It's a two-hour drive选哪个 two-hour walk 和two hours' walk 用英语怎么说 两小时的路程?是two hours’drive还是two hour’s drive