请教five-year-old和five years' old这类有关的,带-的复合名词的用法?为什么五小时的睡眠可以用six hours‘ sleep或者six-hour sleep,后者hour和sleep中间为什么可以不加-?

her five-year-old five-year=old和five years old用法有什么区别啊 是FIVE YEAR OLD还是FIVE YEARS OLD five years old与five-year-old区别 His little brother is ( ) a) five years old b)five-years-old c)five-year-old d) five-year-old 2.Cathy is a ---girl.A.five years B.five-years-old C.five-year-old D.five-year old 请教five-year-old和five years' old这类有关的,带-的复合名词的用法?为什么五小时的睡眠可以用six hours‘ sleep或者six-hour sleep,后者hour和sleep中间为什么可以不加-? 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 five-month-old.和five months old.有什么区别? a five-year-old boy还是a five-year old boy He is a ____ boy .He is a ____ boy .A.five-years-old B.five years old C.five-year-old D.five year old five-year-old是不是只能作定语?而five years old只能作标语?eg：She is a five-year-old girl.She is five years old. 纠错He is five-year-old this year The little boy is only _____ A.five year old B.five-year-oldC.five-years-old D.five old填选项里的 The boy was __________ and______________ his way last weekendA、five-year-old；lost B、five years old；losed C、five years old；lost D、five-years-old；lost a five-year-old boy与the boy is five years old的区别 five-year-old可以做定语,five years old可以作定语吗? 是the old man has a five years old grandson还是the old man has a five-year-old grandson?