a girl shines a flashlight on a mirror & a flashlight emits light ->  when a girl shines a flashlight on a mirror, light will shine on the mirror  when a girl shines a flashlight on a mirror, light will shine on the mirror & a mirror reflects light ->  when a girl shines a flashlight on a mirror, the light will be reflected by the mirror  when a girl shines a flashlight on a mirror, the light will be reflected by the mirror & if an object reflects light toward the eye then that object can be seen -> if the mirror reflects light toward another girl's eye, then the other girl will see the light