请总结一下用an 和a 来修饰的名词 比如 是an 18-year-old girl 还是用a 什么的 谢谢哈

she is an 8-year-old girl 和she is a 8-year-old girl 到底前面是an an onehundred-year-old man用a还是an 是a eight-year-old 还是an eight-year-old 英语翻译She is a 8-year-old girl还是She is an 8-year-old girl. 英语中当名词的所有格修饰名词时 不定冠词a（an）该怎么用?比如这是... one－year-old前面用an还是a what 后面跟的是名词,how 后面跟形容词.修饰可数名词时需要用a/an那修饰的是单数还是复数数 当元音开头的名词被形容词修饰时,其冠词是用an还是a啊? 我是个英语菜鸟,请问8-year-old前面是用a还是an呢/ three-year-old boy 这样的前面用a还是an?两种我都看过.. 18—year—old前面用a还是用an 在感叹句中what 后面跟的是名词,how 后面跟形容词.修饰可数名词时需要用a/an.修是单数还是复数