请问:是a four years old boy?还是a four year old boy?正确要肯定的

请问:是a four years old boy?还是a four year old boy?正确要肯定的 Four Years Old 歌词 This____girl is so lovely.A.four years old B.four-years-girl C.four-year-old D.six-months-old four years old 是时间点还是时间段 请问是six-year-old还是six years old还是six-years-old?(这个空签名有个a ) his father is _ than his mother A.old four years B.as your years old C.four years oldD.bigger your years This is a_boy.He can't look after himself A,four-years-old.B.four-years-olds,C,four- year-old为什么 关于four－year－old－－－children are too young to go to schoolA four－year－oldB four－years－oldC four years oldD four year old答案是A．为什么A是对的?为什么C不对?麻烦分析一下 英语翻译还有,“他四岁”是说he is four years old还是he is four year old? This is a ___boy.He can't look after himself.A.four-years-old B four-years-olds C,four-year-old D four year old 一直分不清有连字符和没有连字符的区别 He is only four years old.是什么意思? only four years old的意思 my four years‘ old son 哪里不对 She was four years old when she began to lean the accordion 对话线部分提问划线的是four years old Little Tom is four years old,but he can r__ a bike. Why is the boy four years old at home but two and a half on buses? When he was four years old,he___sing several English songs?A.could B.can C.may Four years old at home,Two and a Half in Buses and Trains短文翻译