the store and the next sentence is penguin mask or flightless birds and that's kind of a random sentence so the model is asked to predict well that's probably not the next and following this first sentence so you do these two tasks a pre-trained and D can do this unsupervised you don't need supervised data for that you just need a corpus and they do this for a long time with a lot of data and the model itself is giant has 24 I think of these transformer layers so it's giant and then you kind of pre-trained in this