of the top sentence here the man went to mask store right don't don't don't worry about the set and so on just this a man went to a mask store and the models simply asked to predict what's here which word is there so it needs to incorporate information from the right and from the left to do this so that's basically how you train it they simply drop out some of the words some of the time and they they have different techniques so you can clearly tell a lot of work has gone into kind of fine-tuning everything in this model