为什么不能说 a 8 years’old boy?

为什么不能说 a 8 years’old boy? 为什么要说the/a two-year-old boy 不能说two years old boy 为什么不能有a five years old boy 中间没有连字符 求详解 five years old 和five-year-old的区别为什么 She is five years old.不能说成She is five-year-old be动词之后可以加形容词啊 The _ boy is Tom's brother.A 8-year old B 8 years old C 8year old D 8 years' old 请说明理由不知为什么 by next year,he__tweney years old A.will have been B.will be 为什么不能选A She was a ________ woman.a.forty year old b.forty years oldc.forty-years-old d.forty- year-old这个空到底选择哪一个呢?为什么呢能不能详细的说一下呢? ______she swim when she was nine years old?A.Can B.Could C.Can’t D.If为什么不能选A? The house _____ big trees _____ an old man,who died several years ago.A.is surrounded by; belongs toC.surrounded by; belongs to 为什么不能选A The ___man is my farther.A.fifty -one years oldB.fifty -one -year -old答案选择B,但为什么A不能选? how old is the old woman i think she isA.70-year-old B.70 yearsC.70 year old D 70 years old 说下为什么 A____boy can sing the English song very well.a.ten-years-old b.ten years old c.ten-year-oldd.tenth years old请说明为什么? 【初一英语选择题】My friend Jack is a___________boy.A.15-years-old B.15 years oldC.15-year-oldD.15 year old老师说选C,我觉得B也对,难道B不对吗,为什么?谢谢! 两个英语问题,不难1.既然说“我已经六岁了”是“I am 6 years old.为什么不是用过去式I was 6 years old呢?2.We can______something in English.A.say B speak Mr Green is a doctor of ( )and his daughter Ann is ( )college student.A. 50 years old：an 18-year-old B.50-year-old ;an 18 years old答案是A,可是为什么不能选B?请指导我一下!谢谢您! by the time 空格 he was ten years old ,he had begun to make a living by selling newspapers.空格那个地方为什么不能填when 关于I am 11 years old.今天有朋友说可以不可以years后面加上所有格呢?也就是years' old如题,为什么? he is an 8 years old boy 为什么不对