Polar questions, also known as yes/no questions, are those which invite a simple yes/no answer. They begin with an auxiliary verb or modal verb and are usually, but not always, answered using the same auxiliary/modal verb.
- Do you like chocolate? - Yes, I do/No, I don't
- Does she speak English? - Yes, she does/No, she doesn't
- Are you ready? - Yes, we are/No, we aren't
It is important that students learn to include the modal verb after "yes" or "no" as answering with a simple "yes" or "no" will be taken by a native speaker to indicate that the speaker is either being rude or has no interest in the conversation and the conversation will end abruptly with both parties feeling mildly offended. Obviously the speaker can omit the "I do" part if (s)he then goes on to say something else immediately afterwards.
- Does she speak English? No, but she's started taking lessons."
Would be equally acceptable.
Students should also take care to repeat the modal or auxiliary and not the verb. In other words, the answer to the question "Do you like chocolate?" is not "Yes, I like.", but "Yes, I do."
Not all questions beginning with "Did/Are you...?" etc. lead to a simple yes/no answer. One way of getting students to respond more fully is by asking "either/or" questions, for instance, "Did you..., or were you..?"