Answer:
To contradict the message conveyed by the main plot
A subplot can focus on another aspect of the protagonist, or it can follow the story of another main character and his or her development. It can drive home theme and it can aid in world-building. Subplots will enrich your novel and make your story a more compelling read.
"What a beauty!" exclaimed Susie.
Hope this helped.
I phoned him because he was not home.
The second part of the sentence is now dependent on the first as it cannot stand alone as its own sentence.
