a和an怎么用,hour为什么是an

a和an怎么用,hour为什么是an 一个小时为什么是an hour而不是a hour? an hour的不定冠词为什么是an为什么是AN不是A 半小时用英语讲为什么是half an hour而不是a half hour一个半小时用英语将为什么是one and a half hour 而不是one and half an hour? an hour a day怎么造句 half an hour 和a half hour有什么区别? half an hour和a half hour一样吗? half an hour和a half hour一样吗? a hour 还是 an hour?hour 前面到底是用a 还是an? ten minutes seems an hour when one is waiting for a phone call.为什么是用seems不是用seem? 为什么是an uncle和a university? (There is going to be)a birthday party in an hour.为什么是这种格式? We're having a meeting in half an hour.为什么是having如果We have a meeting in half an hour可不可以 half an hour中的half词性为什么是名词? Don't worry.They'll come to help us ________.A.in half an hour B.in a half hour C.after half an hour D.after a half hour答案为什么是A不是B hour前用a还是用an a 和an怎么用,知道是元音音标用an,但是什么是元音音标 One and a half an hour 和An hour and a half 有什么不同