This nice room is the twins' bedroom.( twins-> twims')
The cat is Kate's.lt's Mimi.(没有错呀）
This is Lei Hao s and Bai Jie's classrooms (Lei Hao 's-> Lei Hao ).
The black car is a Chinese car.（an -> a)
Her eraser is very nice.( she -> Her )
He is their father.( they -> their )