It's nice to say thank you to strangers.
Doris holds the door open for Dina as she enters the local supermarket.
Dina wants to enter the store.
Dina thanks Doris for holding the door and wishes her well as she goes into the store.
Dina shuffles past Doris quickly, accidentally hitting her with her bag.
Doris feels good about having helped someone out and has a lovely day.
Doris feels discouraged about  doing a good deed and doesn't do it as often anymore.