1. There aren't two cats in the garden.
2. There isn't a fish in a lake.
3. There aren't three computers.
4. There isn't a mountain outside.
5. There aren't four books on the shelf.
6. There isn't a girl in the street.
7. There aren't students in class.
8. There isn't a poster in the room.
9. There aren't six pencils.
10. There isn't a tomato in the fridge.