First of all I must say - I have not used this book. I'm not going to either. I've read the review of the person that gave this book 4 stars and said it taught him grammer. Well... with the number of mistakes he had in that little review this book couldn't have been too helpful. Don't get me wrong, I'm not going against that person or try to belittle him (god knows my english if far from being perfect), however I do think that after going through a whole book dedicated to grammer rules one should be able to consruct a full present-simple sentence without mistakes. Since I do not believe people are stupid the only conclusion I mast draw - this book is not that good.