The exposition is the very beginning of the story so it should introduce the characters and the setting and maybe introduce a lesson to be learned.
It would be a comprehensive description and explanation of an idea.
It's just telling you to make a sentence where a snack and a show are both nouns. For instance:
I really like watching Spongebob Squarepants while eating Goldfish.
Hope this helped!
Answer: Change there to their.
The main point of turning off dining light is that if you don’t you waste energy and you have to pay a lot of electricity bills