为什么不能有a five years old boy 中间没有连字符 求详解

为什么不能有a five years old boy 中间没有连字符 求详解 fall in love with为什么不能跟for five years?为什么be in love with可以? A Roadmap for Five Years He is no longer the simple-minded man__he was five years ago.A.that B.which C.whom D.what选that 为什么不能选whom呢? the young man has been a doctor _______.A.five years agoB.since five years befoeC.for five yearsD.since five years ago B和D有什么根本上的区别吗?C是 for five year . 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 afer ___he can speak french quite well讲一下为什么其他的不行a five years learn b five years'study c five-year study d five-years learn He sister is ( )than he A.younger five years B.five years younger C.five year youngerD.five younger years She was in college( ).a.five years after b.five years ago c.in fie years d.late five years 关于a ten-day holiday的用法问题!It's five years since we began to enjoy a ( )spring holiday each year.括号里为什么要填ten-day,而不是ten days'还有他俩有什么区别 为什么ten days’前不能有冠词？ I usually ____ a bus to school five years ago.A,take B,took为什么不是take，前面不是有usually吗？ 2.Cathy is a ---girl.A.five years B.five-years-old C.five-year-old D.five-year old when did you start skating?a,since i was five b since five years ago c when i was six d for six years选哪个,为什么? Mike is a _____school boy.A five years old B five--- years -- old C.five--- years old 1.School start at nine o'clock.改错并语法说明 2.He is a five-years-old boy. His little brother is ( ) a) five years old b)five-years-old c)five-year-old d) five-year-old 为什么不能说 a 8 years’old boy? 我想问一道很让我纠结的英语题~I have learned Japanese_______I was five years old.A.before B.when C.after D.since但我真的想不明白为什么不能选D,