It’s a common mistake. We see it all the time, especially on Facebook posts. Posters write SHOULD OF instead of SHOULD HAVE or SHOULD’VE, COULD OF instead of COULD HAVE or COULD’VE. It’s an understandable mistake. Our ears hear the word OF instead of HAVE, especially when the contraction is used. However, it’s wrong. Use HAVE instead of OF. Show everyone your ears don’t fool you.
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