Read and correct the mistakes

1. Whose bag is this? — It's
   [ ].
2. My toy is bigger than
   [ ].
3. This is not my pen.
   [ ]
   is green.
4. It is not a problem, we can give you
   [ ]
   book.
5. They are
   [ ]
   friends.
6. Carol sometimes forgets to wash
   [ ]
   hands.
7. She visits some friends of
   [ ]
   every weekend.