Questions: DBH sets
Do = do, does did, will do, would do, could do
Be = is, are, was, were, will be, would be, could be
Have= has, had, have, will have, would have, could have
Ask one simple tense: past or present, future or conditional
Ask one continous tense: past or present, future or conditional
Ask one perfect tense: past or present, future or conditional