Найдите и исправьте ошибки. 1. these are mr. browens' children. 2. my grandparent's don't work. 3. where are the pupils's bags? 4. mr's black office is here. 5. jane's and mary's brother is having lunch now.

They are Mr. Brown's children.
My grandparents don't work
Where are the pupil's bags?
Mr Black's office is here
Jane's and Mary's brother  are having lunch now