If you want all the rules of writing in English, this is it. And it's not too long, either. It just tells you all the rules, very clearly, gives examples, and has practice exercises. And it's awesome. I was an English major in college. I had a friend who wasn't, but used this book in his business writing and spanked my grammatical behind. So I went to his professor to say I was graduating and couldn't take his class, but could I please buy a copy of the book? He was so tickled (what can I say?) that he gave me, as a gift, both the student and teacher manuals. I am so glad. I've mostly used it as a reference book, and it's a handy one to have. Keep it with your Strunk & White 'Elements of Style'.