yrars old 和 years of age 有什么不同?

yrars old 和 years of age 有什么不同? 18 years old和18-years-old有什么区别 翻译He is 20 years old / years of age. when i'm 4 years old为什么加years old 而at the age of 4不加years old years old 和year-old的区别和用法 fourteen year old和fourteen years old和fourteen-year-old和fourteen-years-old的区别 ten years old 和ten-year-old的区别 three-year-old 和 three years old 有什么区别 three -year-old 和 three years old有什么区别? 11-year-old和11 years old有什么区别 seven years old和even-year-old的区别 12 -year-old 和12 years old的区别 求助：a history of 的用法和 be over+time+years old的用法,能举些例子就更好了! She died of c-----when she was 70 years old I am 12 years old boy of chinese.什么意思 At the age of five years old RT T___ of years old ,women wore silk and cotton clothes 问一下seven-years-old和seven years old有什么区别!