在英语中表示岁数的year和years old有什么区别?

在英语中表示岁数的year和years old有什么区别? 11-year-old和11 years old有什么区别 three-year-old 和 three years old 有什么区别 three -year-old 和 three years old有什么区别? year-old和years old的区别 fifteen-year-old 和fifteen years old 有什么区别?包括他们各自的用法 16-year-old和16-year-olds和16 years old有什么区别? 英语中年龄的表达法16-year-old 与16 years old 的区别,Lucy is 16 years old. years old 和year-old的区别和用法 six-year-old boy和six years old boy 有什么区别?一样么?为什么? five-year=old和five years old用法有什么区别啊 six-year-old和six years old用法有什么区别?