How many minutes in an hours 为什么用an而不用a呢

How many minutes in an hours 为什么用an而不用a呢 How many minutes are there in an hour?（回答） are,minutes,how many,there,in,hour,an how many minutes in 2 hours 英语中的hour前面为什么用an,而不用a? there is [no ]apple in the box.为什么用no而不用no　 an呢?具体解释一下there it is an oranre pen为什么用an而不用a 短句求翻译As a general rule,for how many hours will an "eight day in how many minutes how many hours are in a day My brother is a student in（ a ）university.为什么不用an呢? amazing 为什么用an不用a