5 предложений с конструкцией there is there are
There is a computer in this room. There is a mouse in the pocket. There are cars on the parking lot. There is a button in the box. There is a sun in the sky.
В этих предложениях правильнее было бы использовать the. Но так тоже верно, конечно. Хотя в последнем предложении допустимо использовать ТОЛЬКО определенный артикль! Солнце, оно одно, поэтому THE SUN.
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