None. The letter s in the word greetings is part of this word. It doesn't show an ownership.
Yes. "Season's Greetings" is correct.
Yes.Greetings of the season => Season's Greetings. Possessive usage.
Yes, because they are the greetings of the season.
It is technically a possessive, Season's Greetings(greetings of the Christmas season), but on posters, banners, and cards the apostrophe is often omitted.
If the word ends in apostrophe s or ends in s apostrophe, then there is NO space before or after the apostrophe, but always a space before the next word.
It is technically a possessive, Season's Greetings(greetings of the Christmas season), but on posters, banners, and cards the apostrophe is often omitted.
No, only use an apostrophe when using a contraction or a possessive
No, the word "regards" does not contain an apostrophe. It is a plural noun that means best wishes or greetings.
Personally, no. But it's not incorrect to put the apostrophe.
No. If the sheriff possesses something, it is the sheriff's with an apostrophe before the "s."
Before the 's'.
If it is required, the apostrophe would come after the Z but before the S. "This is Mr. Buzz's stinger!"