Исправь предложения. например;it`s a book.-it isn`t a book. it`s an exercise. (теперь наши слова.) 1) they`re chairs

 1) It`s an exercise. - It isn\'t an exercise.  2) They`re chairs - They aren\'t chairs. 3) It`s a blackboard. - It isn\'t a blackboard. 4) They`re old. - They aren\'t old. 5) It`s brown.- It isn\'t brown. 6) They\'re comfortable. - They aren\'t comfortable. 7) It\'s a pen. - It isn\'t a pen.