I like this book, along with The Oxford French Vocaulary Builder (also in cartoons) - this got me back into French grammar and improved my writing in a week. Each chapter covers a different topic using cartoons and stories. Although it is clearly designed with older children in mind it doesn't grate on adults. I was amused by some of the stories. The exercises are excellent but they do require writing so some aren't particularly easy to do on the train. However, there are answers and there are plenty of exercises, often broken up into sections. There is a verb table and excellent vocabulary at the back so you don't need a dictionary - a plus for those like me wanting to use train journeys to get the work done. I recommend it. I bought larger and more substantial grammar books too but this one fits into my briefcase and it's fun; it's also useful for quickly checking on something I need reassurance about.