It doesn’t say how. It’s a false promise. A pretense. Grammar provides rules by

It doesn’t say how. It’s a false promise. A pretense.
Grammar provides rules by which we disambiguate sequences of phonemes into words phrases and sentences (transactions) sufficiently to convey unambiguous meaning within the broader context of the discourse.

So grammar is used for (a) disambiguation (b) model formation (c) predicting testing (falsification) in that order. And Q&A for further recursive disambiguation until sufficiently unambiguous decidability is achieved by determination of possibility(truth) or impossibility (falsehood).

I’m kind of wondering if you’ve done any computer or AI work yourself because this is pretty basic nonsense there. I’m just adding neurologically what happens and in what sequence.