Describe in specific detail the contrast between the two families, the Earnshaw's and the Linton's . Focus on the differneces in personality traits of the family members and in how they treated each other and other people. Wuthering Heights
These sites should help you with this:
http://www.sparknotes.com/lit/wuthering/
http://www.bookrags.com/notes/wh/
http://www.antistudy.com/free_book_notes/Wuthering_Heights.php