sorry for the repetitive questions! otherwise thank you for taking the time to check my answers.
Underline the gerund, some do not have a gerund if so write ''no gerund.''
1. Sketching is fun for me.
Sketching - Subject
2. Marya exercises every day by swimming.
Swimming - Object of preposition
3. She and I are singing in the chorus tonight.
No gerund
4. Of all my interests, I care most about reading.
Reading - object of preposition
5. Traveling comes second or third on my list of favorites.
Traveling - Subject
6. What is the most interesting hobby for you?
No gerund
7. Her other leisure activity is painting.
Painting - Predicate noun
3 answers
3 is wrong. The others are correct.
You're right. 3. does not have a gerund. Singing is part of the verb, are singing.
All are right.
All are right.
I disagree on #3, and that's my story and I'm sticking to it. :)