下列各句均有一处错误 请找出并改正

months
What day is his birthday?
years
There are three rooms in our classroom.
How old is the girl?

第一句：month应为months
第二句：date应为day
第三句：year应为years
第四句：three应为third
第五句：how后面应加上old

There are twelve month in a year.(month-> months)
What's the date of his birthday?(birthday-> birth)
Mrs Brown's son is eight year old.(year-> years)
Look!The three room is our classromm.(room-> rooms)
--How is the girl?
--She's five. (five-> fine)