i just wanted to clarify something. It has to do with the use of vocative commas. Vocative commas are used when you are separating a person’s name from the rest of the sentence, such as the following:
John, it’s good to see you.
You would use the vocative comma instead of writing: John it’s good to see you.
You also need to use a comma with parenthetic expressions. An example of this is a follows:
It is my opinion, and I travel once a month, that flying beats driving.
Please note that, if you use one comma in the sentence, you must use both. Sometimes students don’t use any when writing parenthetic expressions and that can be confusing at best.
Hope this helps!