是a old man还是an old man?如果是an的话,那为什么university是用a呢?

是a old man还是an old man?如果是an的话,那为什么university是用a呢? an onehundred-year-old man用a还是an 是the old man has a five years old grandson还是the old man has a five-year-old grandson? 是a eight-year-old 还是an eight-year-old the old man is a expert 这里是a还是an? 英语翻译I'm very very old,an old man. 和蔼的老人是a kind old man还是a kindness old man 是 I see an old man on the road还是 I see an old man in the road old women单数形式是a old women 还是 an old women? AN OLD MAN 翻译 being an old man now 和having been an old man now 选择题选项（ ）,he prefers a quiet life.a.being an old man now b.having been an old man now为什么不能选b.是b选项本身有问题吗?还是什么? ¿＿＿old man 填a还是an,并说明一下原因,¿＿＿old man填a还是an,并说明一下原因,怎么是选an呢？old是形容词，man是名词，man以辅音开头 a eleven-year-old还是an eleven-year-old 是“I saw an old man fall down”还是“I saw an old man fell down”已看到摔倒的全过程 （ ）old woman是填a还是填an 是a one-year-old boy还是an one-year-old boy A girl helped an old man,and the old man was excited译成中文 Next door to ours _________,who has just return from abroad.A.where lives an old man B.where does the oldman liveC.lives an old man D.does an old man live答案是C请问A 为什么错