Situation: A person just dropped a ceramic plate, and now it is broken on the floor. Question: Why do you think this person feels sad?
The plate broke, maybe it was special to the person. Maybe they don't have any other plates.
Situation: A person is holding a big, golden trophy. They have just won a competition. Question: Why do you think this person feels happy and proud?
He won a prize, he worked hard and won the trophy.
Situation: A person has been waiting for a long time in a very long line. They have a lot of other things to do. Question: Why do you think this person feels frustrated?
The line will take so long, he will be late to another appointment/activity.