This book of more than a thousand pages has every topic that could possibly be on the ACT. The topics are explained in a clear, concise manner. But there are so many topics that their explanations are almost too concise: Two or three sentences of explanations are given and a couple of examples. The format of the examples are in a No and Yes format for the English section. The drills in the English section and Science have good explanations with them. But in the Math section, in which work might be needed, there are no explanations, only answers. The Reading section has no explanation either. The diagnostic test and four other tests gives you great explanations for each topic, though.

Don't get me wrong, some topics are explained well because of the many sub-categories. But other topics are really sketchy on the details. Also, in the English section, the book expects you to memorize all the "by-the-book" terms, like superlative and present perfect. I had never even heard of those terms until I had taken a Spanish class. Moreover, other books might help you memorize things by acronyms but this book if just full of dry information.

If you have to take the ACT in a couple months or weeks, this is a very bad book for you. With all this info, you would need a year to get through it all. Moreover, there is so much stuff that you really don't need for the ACT. This book gives you years worth of information. You can really tell from the science topics of astrology, meteorology, physics, etc.

At least now I understand the elusive diffence between who and whom.