为什么是an unexpected而不是a unexpected,un的u不是发^音吗,发音都不是元音

为什么是an unexpected而不是a unexpected,un的u不是发^音吗,发音都不是元音 为什么是A UFO而不是an UFO? 为什么是a unique opportunity 而不是an expected an unexpected u... 一个小时为什么是an hour而不是a hour? uniform为什么是a uniform而不是an uniform? 为什么是a European country 而不是an European country uniform为什么是a uniform而不是an uniform? 为什么是an apple a day而不是a day an apple Alice,why didn't you come yesterday?I _,but i had an unexpected visitor.A had B would C w...Alice,why didn't you come yesterday?I _,but i had an unexpected visitor.A had B would C was going to D did答案为什么是选c,B怎么不行呀, i bought them (each an ice cream)为什么是each an ice cream而不是an each ice cream how do you spell it it is eraser.it is 后面为什么是an 而不是/? racing drivers have reached speeds over 600 miles an hour.这里为什么是speeds而不是speed? He speaks English as though he were an American.为什么是he were而不是he was 为什么是A UFO而不是an UFO?NBA他的开头因素是/en/那他不加an 为什么是opening而不是openning? 为什么是一氧化碳而不是氧化碳 为什么是指南针而不是指北针?