英语初二a member of后面是加名词复数吗,例句有吗the twelve twelve-year-olds为什么要

Craig创办的 the twelve twelve-year-olds怎么翻译 a twelve-year-old和 twelve years old有区别吗?如果有是什么区别 a number of 后面要加可数名词复数,为什么经常加people.people不是不可数名词吗? 63.December is the ___________ (twelve) month of a year. We are a member of the Computer Club.中的a member of 要变成复数吗? Ben is a ______boy 是twelve-year-oid,为什么不是twelve-years-oid,详细 Ma Yanli is a twelve-year-old girl.为什么要加- there are twelve month of a year Twelve-year-olds should not (A.allow B.be allow C.allowed D. neither of them is {a} member of the league要加"A"吗?为什么? is one of the 是加名词复数吗 有人说a lot of 后面只可以加可数名词复数 那么为什么有 a lot of money呢?