First, the advanced version:

And the slightly dumbed down version:
僕、疲れた。 食べ物を変わりに噛んでくれるかい?

boku, tsukareta. tabemono wo kawari ni kande kureru kai?

“kai” is a more informal and friendly way of ending a question, instead of just plain “ka.” Or, if you use it improperly it could also be used to pick a fight, because it sounds like you’re talking down to the person.