Singular vs Plurals

Some (a)   (student/students) studied for their exams.

Sandy watched a (a)   (film/films) last week.

Three (a)   (woman/women) are working in the office.

Peter wrote an (a)   (essay/essays) for his history class.

Marie ate two baked (a)   (potato/potatoes) for dinner.

Many (a)   (man/men) like playing football.

Mona got a new (a)   (dress/dresses) for her birthday.

Do you know those (a)   (person/people) over there?

There are a lot of (a)   (animal/animals) in the zoo.

My two (a)   (child/children) hate eating vegetables.