Say to what categories these books belong: 1.oliver twist 2.kashtanka 3.life of leo tolstoy 4.frankenstein 5.gulliver's travels 6.little mermaid 7.three musketeers 8.the time machine 9.ivanhoe 10. little red riding hood 11. around the world in eighty days 12.hound of the bskervilles 13.robin hood and the sheriff 14.three men in a boat

Books for children: Oliver Twist, Kashtanka, Gulliver's travels, The Little Mermaid,  little red riding hood, robin hood and the sheriff.
Books for teenages: Frankenstein, The Time Machine, Ivanhoe, around the world in eighty days, hound of the bskervilles, three men in a boat.
Books for adult: Life of Leo Tolstoy, Three Musketeers.