i dont understand this question. but you use it in a list or when you add something extra to your sentence, as long as it makes sence without the extra bit of information.
before
It depends on the style guide you are following. In American English, the comma before "and" in a list is known as the Oxford comma, and it's optional. In British English, the Oxford comma is typically not used. It's essential to be consistent in your use of the Oxford comma throughout your writing.
No, a comma is not always required before "but" in a sentence. It depends on the structure of the sentence and the context in which "but" is used. If "but" is connecting two independent clauses, a comma is typically used before it.
No, a comma is not necessary.
You would use a comma before it. Xerox, Inc.
no
Before. If you are listing three or more things in a sentence, there are two ways to use commas. The most well known way is to not use a comma. Ex: Paul likes fishing, swimming and sailing. If you use a comma, place it before "and." Ex: Paul likes fishing, swimming, and sailing. This is called using an "Oxford comma."
You do not always need to use a comma with the word sobut if you do, it is best to only use the comma before the word. An example is "The travellers faced a long drive home, so they decided to stop at MacDonald's first."
if the main or most important part is before the main parts you use a comma, but if it is after then no comma
no
A comma is used after the introductory word when using AAAWWUBBIS (as, although, after, when, while, until, because, before, if, since, even though). For example, "After he finished his homework, he went to bed."
Yes, you can put a comma before except. Example of a comma before except in a sentence- She can do it, except that the mountain is too steep