particular form there's this skeleton and in this skeleton there is this block and it's always repeated and you're basically your task is to determine what this block should be so this block has an input node a and an output node D and two intermediate nodes and what you have to do is basically you have to determine these connections right here so there are six connections and for each one you have the option of putting different things there like you can see you put can put a convolution you can put the identity function which is a skip