When he wrote this book, it helps to think of him in the past, but when you have forgotten your old story it reminds him a sad story that ever made him regret.
When he wrote this book to help him recall the memory of the past, but never forget that when I remember an old story, it reminded him of the tragedy that had made him sad.
When he wrote this book to help reminds him of memory in the past have forgotten, but when the old as it reminded him of something sad ever made him sad.