no. if but before is a sentence on its on and after but is a sentence on its own then put a comma before but.
after
befor
Before. ex. I had every intention of going to the store, but I forgot.
Punctuation is dictated by the meaning of your sentence, not by the presence of particular words. A comma indicates a brief pause. Say your sentence aloud, and where you find that you naturally pause briefly, you will probably find that a comma is appropriate. Other people may punctuate the same sentence differently. That is not necessarily wrong. A lot depends on the context: whether it is formal, informal, written, spoken, and so on. Here are some examples: 'There was nobody in the house but my mother.' (No comma) 'I like cheese, but my sister can't stand it.' (Comma before 'but') 'I would prefer you to stay at home but, if you do go out, please wear a warm coat.' (Comma after 'but') 'I would prefer you to stay at home, but if you do go out, please wear a warm coat.' (Comma before 'but') (The last two examples convey slightly different shades of meaning.) It's perfectly possible to have a comma both before and after the word 'but' if you think the sense requires it, but you should be wary of having too many commas in one sentence.
No, before ... as in: Marcus Welby, MD
Yes. You should write it at John P. Doe, MD
Not necessarily. Commas are a feature of sentence structure.
before
No, a comma is not necessary.
no
You would use a comma before it. Xerox, Inc.
if the main or most important part is before the main parts you use a comma, but if it is after then no comma
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
No
no
no