Сделайте предложения отрицательными:
1. There is a cat on the sofa.
2. There are tables in the class.
3. There is an armchair between tables.

1. There is no cat on the couch.

  2. There is no table in the class.

  3. There is no armchair between the tables

Вроде бы так

1. There is not a cat on the sofa.

2. There are not tables in the class.

3. There is not an armchair between tables.

Объяснение: