Somebody asked me about this the other day:
An apostrophe is never used to create a plural. It has only two uses: contractions and possession.
Example of contraction: “It’s” for “It is”; “you’re” for “you are”.
Example of possession: “Rush’s microphone”; “Fred Thompson’s speech”.
Note: some possessive words, like “his”, “hers”, “your”, etc., have no other use and therefore require no apostrophe.
He knows.
We just ignore it. LOL!!!