One boy laughs at another wearing an elf hat in the locker room .
People are in the lockerroom .
One boy laughs at another wearing an elf hat in the locker room.
People are in the lockerroom.
"One boy" and "another" imply that there are at least 2 people in the locker room, so the boy and another can be simplified just as "people".
`` One boy '' and `` another '' imply that there are at least 2 people in the locker room , so the boy and another can be simplified just as `` people '' .