Come on, guy's. Stop using apostrophe's for plural's. It makes your employee's look uneducated. I've seen this multiple time's and it really get's on my nerve's. Apostrophe's should only be used if something belong's to someone ("dad's", "Linus's", "Greg's") or if the word i's an actual contraction, such as "don't", "aren't', "haven't", etc. The grammar police (and your school teachers) are watching. And yes, "teachers" is correct!