Answer:
It plays a major role because it's easier to read by separating phrases.
Step-by-step explanation:
For example, if you invited your grandma to eat dinner, you could say "Let's eat Grandma" but that sounds wrong. You're addressing your grandma, not eating her. So you would say "Let's eat, Grandma." with a comma to show separation. Also, commas are used like I just used it, after a transition word. And if there is more than two things that you are referring to, you use commas. For example, "pickles, cats, and dogs."