I think we all agree that grammar books are very helpful when trying to learn the rules of a language. However, be aware that most grammar books, even the latest editions, merely repeat what the rules were 20 or 50 years ago. The truth is, language changes.
Take a look at a short video clip about this topic by clicking on the link below:
Is there a difference between what the grammar rules of your language say and how the people really speak the language? Can you send in some examples?