This document provides information and examples about teaching modals, including had to and could. It explains that modals are used to talk about obligations, suggestions, advice, and expectations. Specific uses of had to as describing past obligations and necessities are explained. Examples are given for simple modals in the present and future and perfect modals in the past. Strong necessities are distinguished using must, have to, and have got to. Had better is explained for giving warnings. Should is described as offering advice. Could and might are presented as being more gentle than should. Suggested classroom activities for practicing modals through surveys, sentence pairs, and conversation cards are outlined.