(Image source: Exomid)
People who have spoken English from childhood need to be aware that it's a darn hard language, and cut some slack for people who are struggling to learn it. Mistakes happen, and we can usually figure out what someone is really trying to say. Still, some English mistakes fall way over the "oops" category and into serious puns. The picture above is obviously a sign for the men's restroom, but labeling it with the singular "man" turns it into a superhero. That's something you wouldn't know if you're not familiar with the usage. So what we get is the world's worst superhero.
Sometimes all it takes is a simple misspelling, but if there's no one around who can spell in fluent English, the results can be disastrous.
(Image source: ClinicalIllusionist)
A list of 50 funny English mistakes at Bored Panda include not only misunderstandings and misspellings, but also bad machine translations and most egregiously, language mishaps from native English speakers. Those are the ones that will make you facepalm over and over.