Parallel Structure Co-ordinating units of writing must all be of the same grammatical kind. This is what is referred to as preserving parallel structure. For instance, nouns must match with nouns, ...

This is particularly true when it comes to lists. Make sure each one has proper parallel structure. Not Parallel: Kids like singing, chatting, and obsessively check their phones.

But this is correct parallel structure too, because all three stems attach to that shared subject the same way. What would happen if we mixed things up just a little in our first Brad sentence?