Harry Potter and the Half Blood

I am reading "Harry Potter and the Half Bood Prince" by J.K. Rowling. This book has all the same characters as all the rest of the other Harry Potter books.Of course this includes Harry Potter and Ron Weasley and Hermione Granger. This book is about when Harry loses his potions book and has to use an old copy. It turns out that the old copy of the book has tons of spells and clues in it. One spell is called sectumsempra. When Harry was walking down the hall he heard someone crying . It was Malfoy. When Malfoy saw Harry he got mad and shot a spell at him. Harry shot the sectumsempra spell at Malfoy. It was as if a sword had cut across Malfoy. Harry felt terrible because he didn't know what the spell could do to someone. Find out more by reading the book.