1. Observe the Picture clearly.
2. Look up for the kind of environment in which the scene or action is taking place.
3. Look up for clues to substantiate the environment.
4. No. of characters shown, their dress, their age ,relationship between those characters, facial expressions. Are they smiling? Is there any sense of urgency on their face? etc.,
5. Change in relationship between characters might lead to a different cause. A father and a son might discuss something where as a teacher and student might discuss something.