How do commas work within sentences?

Use a comma between two long independent clauses when conjunctions such as and, or, but, for, nor connect them. Example: I have painted the entire house, but she is still working on sanding the floors. Rule: If the clauses are both short, you may omit the comma.

Commas are used when you are referring to more than 2 thing when you are referring to only 2 things then and is uses . It can also be uses in sentence, when the type of sentence is same but it has 2 parts in it
Ex- please bring me cup, tea, plate, and chips

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