A much needed addition if you're using the Bob Jones Grammar & Writing for 9th grade 3rd Edition. There are times when the student book doesn't clarify what it is they are to look for so the student has to go to this book to look up that specific thing. For example find the "predicate noun". It may not give an explanation to the student what that is so then they have to go to their handbook and look it up, much like a dictionary. I'm very glad that I bought this book, like I said earlier it is a great companion to the Bob Jones Grammar & Writing for 9th grade 3rd Edition.