My instructor who shall be nameless (Jerry Bream) always insisted on me taking a boiled sweet from him while I was in the middle of the most complicated manoeuvres - like on finals etc. How could I take, unwrap and put in my mouth a sweet when my hands and legs were doing fifty to the dozen? What a marvellous man.
By the way, my lovely wife just couldn't crack landing so the instructors wisely passed over that and finished the rest of the techniques, she finally went solo after about 75 hours by which time she had covered nearly everything else. If you get stuck with one thing it's often wise to put it to one side and return at a later stage - methinks.