This question (How to shoot nice shots in indoor nightclub?) made me think about composing arbitrary groups of people. Usually a few people is manageable, but with more people, I don't know what to do with them in the frame.
People seated in audience.
People mingling in a reception.
People dancing at night club.
People standing in circle.
I expect this is a challenge that event, wedding, and street photographers deal with regularly. How do you handle it? How do you compose photographs with un-posed groups of four or more people?
Any artistic framework is fine. For instance, selective focus is fine. Not everyone has to be in focus, as long as the final image looks good.
Diagrams or example photos to illustrate concepts would be helpful.