When Happiness Knocks on the Door is a broadcast script. Broadcast manuscripts include recitations of classic American poems, and line manuscripts are words spoken by characters in film and television performances. When Happiness Knocks on the Door is a youth inspirational poem recitation script, so When Happiness Comes on the Door is a broadcast script, not a line script. The content of When Happiness Knocks on the Door is: When happiness knocks on the door, I invite it into the house, like a reunited friend. However, I will tell it that it has gone to the wrong place. My friend, you should follow the direction of the dark clouds crying and cross it. That river of blood.