When you're learning another language it's important to know how the grammar of your own language works first. You may use English just fine, but understanding it with terms like "predicate" and "direct object" and "causative" may not be so easy.
English Grammar for Students of Japanese is a reference book you can either read through in one sitting or use to look up specific explanations during your studies. There are explanations for each section of the English language and how they relate to Japanese. There are even example sentences, extra notes, as well as summaries and reviews with an answer key in the back of the book.
If you're having trouble understanding Japanese grammar in relation to English because of linguistic terms or because you never learned it, this book helps bridge the gap.
Unfortunately, it's not formatted well and there are a few English typos here and there. Another issue is all of the Japanese is presented in romaji. But it's a very useful reference if you haven't taken an English class in a while or if your native language is something else.