Re-read books
A really good book is one you will want to read a second time, even though you know how it comes out. A great book is one you will read 3, 4 or more times (or every couple years or so). A mystery novel/story which you read over and over is a great work of literature, and I have a large number of them which I have read 10 or more times and expect to keep on reading every so often. A serious reader is one who can read a book more than once and enjoy it. We are a vanishing breed already (seems as though few young people read books much any more for pleasure) and may get even scarcer as the net and the TV and talking books replace our dear, cherished hard-copy books.