Frankly, without a positive marker your training isn’t going to go far at all. It’s how you, the handler, let your dog know it’s doing correctly whatever you are trying to teach it.
To you, the human, a positive marker is simply your praise word. It’s very important in dog training. And in our human world as well. How else would we know we doing something right?
Here’s a few examples, with which you are probably familiar:
It doesn’t matter what language you use for your marker, just be consistent, because when you aren't using clear verbalization, dogs can get confused and you, the human, get frustrated.
Dogs can learn in any language and some often learn two in a bilingual household.
And if you’ve done your homework, that word or combination (keep it simple!) will have really high value, which will encourage Phydo to repeat that behavior you just marked again when he is part of the same scenario.
Without a positive marker your dog has no clue just how important what it just did actually was to you. Of course, the more you repeat your marker appropriately and in time, the faster your dog will learn that behavior. Yes, it’s all about repetition, repetition, repetition. Proper praise can go such a long way.