After Clint Eastwood's RNC convention speech, President Obama tweeted as follows:
Did he break any apostrophe punctuation rules? I am guessing he didn't as I haven't heard any objections to it. I am assuming the apostrophe is used to show the omission of letters, as in “This seat is taken”. I am confused about the usage as the apostrophe can also be used to form the possessive of the noun seat, as in
My seat's cushion is red.
Can the apostrophe usage change the meaning of a word based on the context of a sentence? Are there other examples for this pattern?