a way of doing drills with a partner whereby the two people are alternately student and coach first Joe is the coach and Bill is the student, then they change and Bill is the coach while Joe is the student, and so on. And then they would do that maybe for three hours and take a turnabout, you see? -TrainingDrills Demonstrated (5 July 1957)by turns; one after the other in regular order.a way of doing drills with a partner whereby the two people are alternately student and coach first Joe is the coach and Bill is the student, then they change and Bill is the coach while Joe is the student, and so on.the action of doing something to someone exactly as that person has done to oneself or another.