1. They aren't having lunch.
2. She isn't doing housework.
3. He isn't having a shower.
4. They aren't playing football.
5. Dog isn't barking.
6. Masha isn't reading magazines.
7. Marina isn't wearing skirts.
8. They aren't visiting their parents.
9. Kris isn't working.
10. She isn't sitting on a sofa.
Объяснение:
Т.к. это отрицательные предложения, то к "to be" добавляется not: is+not=isn't, am+not=am not, are+not=aren't.
