a half hour one hour对不对?

one and a half hours 还是hour half an hour or a half hour? a half hour还是half an hour? half a hour one and a half hours 和 an hour and a half 就是说 超过一个小时候 hour One and a half an hour 和An hour and a half 有什么不同 one and a half hour看做单数还是复数?half an hour half a sandwich,half hour,one and a half hour.这些half的用法都不相同, half an hour 与 one half hour区别 one hour and a half谓语动词为什么用单数? one and a half hour 是否要加s one hour and a half加’s 还是s’