Grammar Book for Desperate High School Student

Hi,

I went to a Chinese local school during lower school and then transferred to an American school. Now, I'm a high school student in California. I can read and write like any other high school student, but the problem is I always use my common sense.

This is becoming a serious problem now, because in AP English, if we have one "common grammatical" error in any of our writing pieces, we cannot get above a C. This also applies to the AP Exam writing prompts, which I am having trouble with.

Is there a book that someone would highly recommend to me? I tried Grammar for Dummies, but it's actually too difficult for me. I don't even know the eight parts of speech for example, because I simply don't have a foundation in grammar. Also, Grammar for Dummies doesn't have solid exercises or answers to check. So, I need a book that starts from the bottom basics, but has solid exercise drills and answers.

Thanks for any help in advance.