Question

英语高手 帮忙 two-year-old 与two years old有何区别

这题应该怎么选，说明理由。谢谢
The river through our city,which is about______,is clean again.
A.6000 metres long B.6000-metre-long

Answer 1

two-year-old 相当于一个形容词， 意思是2岁大的，比如说 She has a two-year-old daughter. 但是用two years old 就要说 Her daughter is two years old。

Answer 2

two-year-old 作定语，前置
two years old：表语，后置

Answer 3

two-year-old 是形容词，放在名词的前面She has a two-year-old daughter。two years old是两岁的意思Her daughter is two years old。

Answer 4

she has a two-year-old child.

her child is two years old.