Hello! I wondered which was grammatically correct: "There were cats, pigs and dogs in the house," or "There were cats, pigs, and dogs in the house." My girlfriend and I could not decide if a comma had to be after pigs or not, or if it was fine to use either.
Oh boy. You’ve stumbled on a dilemma in the English speaking world, and one that is hotly debated. The comma in question is known as the “Serial Comma” or “Oxford Comma,” and different people will have very different opinions on whether or not it should be used.
My personal opinion is that the serial comma should be used, as it eliminates confusion in all lists. However, some people say you should only use the serial comma in instances where not using it would lead to confusion.
In the example you gave me - well, you’re both right. And you’re both wrong, depending on the style guide you’re supposed to be following. (Protip: If you’re writing academically, be sure to look up the Oxford Comma in the style guide you’re meant to be following, and ask your instructor about their preference.)