"Don't walk! Run!"
I think I understand what you had. Remember that when you discuss these sentences on these forums it does not show what kind of exercise you had. Was it one that gave you the English and then said, "_____! yIqet!"? Then you had to type in the Klingon translation of "Don't walk!" I think you understand now, but in case anyone else comes along and still doesn't get it: You shouldn't switch who you are talking to in the middle of an exercise unless there's some indication that you are switching (like in some of our question and response exercises). So either use yI- for both or pe- for both. Since it already gave you a yI-, you should also use yI-.