Hey Pandas, What Grammar Mistakes Annoy You The Most? (Closed)

From the debatable Oxford Comma to subject-verb agreement, simple grammar mistakes often trigger pet peeves, upset the Grammar Queens, and cause confusion. What horrifying grammar mistakes are you bothered by?

#1

“should of”
I know some words are difficult to write when you just heard but never have read them. But this doesn’t even make any sense grammatically. Also everyone(?) learned this as a child…

#2

“How (…) is like”. Say “what” and “like” or say “how” but don’t say both, dammit!