the windows are big and the wall are white哪里错了

the windows are big and the wall are white哪里错了

wall是可数名词，这里用了单数，那么为了主谓一致，后面的be也应该使用单数形式，即is而不是are。或者把wall变成复数也行。

look at the photo of the twin's room. the walls are white and the windows are big. on the wall you can see an old photo of the family. their mother is standing. she is a teacher of english. she is in a red coat. their father is behind her. he looks young.