Sometimes, but not always. There is no one single rule that applies to "but." ----
A period should come before the footnote at the end of a sentence, while a comma should not.
If a comma is needed, it normally comes after parenthesis.
You should put a comma before a person name if you're talking directly to them. ex- Please come here,Lily.
No
"Inc" is not a word, it's an abbreviation for "Incorporated," and there should be a comma before it.
Yes
The comma would come after it.
No.
No.
NO
no
Return to sender does not require quotation marks or a comma.