My advice is not always so logical and consistent. But then, love is not logical and consistent. So why should my advice be? If you want that kind of thinking, go to a computer. Computers are always logical and consistent, and you see how often they get proposed to.
The only way to learn a language properly, in fact, is to marry a man of that nationality. You get what they call in Europe a 'sleeping dictionary.' Of course, I have only been married five times, and I speak seven languages. I'm still trying to remember where I picked up the other two.