Don't go by a rule book.When learning a language, don’t accumulate rules in your head.
Now, I realize that this advice is wildly counter-intuitive. But consider.
Every rule that you learn is just one more thing to remember. The more of them that you learn, the greater is the chance that you forget them.
And even if you never forgot a single rule, do you think you’d ever learn all of them? No one has, even the top linguist ever. There's no end to them. They are continually being discovered.
But the worst thing about rules is that they clog up your mind. They are worse than cholesterol on the brain. Every extra rule demands a larger and larger lexicon of material to refer to before you open your mouth or touch a keypad.
They inhibit you from using the language. You ask yourself: Is this right? Is that wrong? Is this an exception to the rule? Does this application of the rule conflict with another rule?
Final point: How many rules do you know and think about when you use your own language? None, right?
Do you ever stop to think about when to use the article 'the'? You know that there are about 63 rules just about that word alone, didn't you?