functionality for downstream tasks or for transfer and so you know we could compare for instance the probability of the sentence the cat sat on the mat so the probability of the sentence the cat sets on the mat and you know we would expect that let's say we somehow have the true function here we don't know how to learn it yet but we just assume we have like the ground truth of the probabilities of these two sentences well it should assign more probability to the grammatically correct one and that gives you something like grammar