Whose cars are these? These are her cars (or only They are her car)? Is it a mistake to answer this way: Whose cars are these? These are her cars (or only They are her car)? I have come across the grammar rule that only the second variant is possible i.e.: -Whose cars are these? - THEY are her cars. But I started looking some exercises I've found the exercise for translation with the keys like these: 2. What are these? — These are black bags. 3. Who is this? — This is my sister.15. Is this your cassette? — Yes, this is my cassette. 1. Whose cat is this? — This is my cat. 2. What city is this? — This is Madrid. 5. Whose apples are these? — These are not my apples, these are your apples. 6.Whose brother is this? — This is his brother. 7. What are these? — These are your apricots. \