Помогите надо составить 3 предложения с конструкцией This is и There are

There is a book on the table - There are four books on the table There is a dog in the garden - There are three dogs in the garden There is a pencil in the box - There are five pencils in the box There is a teacher in the classroom - There are teachers in the classroom There is a ball on the floor - There are two balls on the floor