a eleven-year-old还是an eleven-year-old

a eleven-year-old还是an eleven-year-old 当an eleven-year-old girl中eleven是数字11时用a还是an当an eleven-year-old girl中eleven是数字11时前面用a还是an 请问是an eleven-year-old boy还是an eleven-year old 是a eight-year-old 还是an eight-year-old Bob is (a) eleven-year-old boy.为什么用a不用an? Don’t complain to him.You know he is _____ boy.A.a three-years-old B.an eleven years oldC.an eleven-year-old D.only three year old 为啥? Ben is a _______ student A．twelve years oldB．eight-year-oldC．thirteen-year-oldD．eleven year old a five-year-old boy还是a five-year old boy a twenty year old boy对还是a twenty years old boy对哪个等于 a twenty-year-old boy? 是a one-year-old boy还是an one-year-old boy a 11-year-old boy还是an 11-year-old boy 英语翻译She is a 8-year-old girl还是She is an 8-year-old girl. I am eleven year old.（改错） one－year-old前面用an还是a 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? Don’t talk to Alicia like that.She is only _____ eleven-year-old kid.A./ B.a C.the D.An an eleven year old 和 an eleven-year-old用哪个?为什么