1. I'd like you to meet my family.

Question

2. This is my dad, mom and little brother.
3. This is my dad, my mom and my little brother.
4. This is my dad. This is my mom. And this is my little brother.
5. These are my dad, mom and little brother.
6. These are my dad, my mom and my little brother.
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From #2 to #6, which ones are grammatical? Can we use all the expressions

Answer 1

All are acceptable. I think we might use #5 or #6 when pointing to their photographs, the others when introducing them in person.

Answer 2

Others disagree, but I advise using the "Oxford comma". Your mom is not also your little brother. Use the comma before "and" in a series to make it clear.

Answer 3

Reed is correct. You should use the Oxford comma every time — that is, put in a comma before ‘and’ every time. Having it there avoids misinterpretation.

Answer 4

Here is an example of ambiguous wording when the Oxford comma was left out:
https://www.nytimes.com/2017/03/16/us/oxford-comma-lawsuit.html

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