Ryan of the Dead Parrots posts an “irregardless considered harmful” memo. My personal all-time language peeve is people who seemingly can’t tell the difference between “it’s” (the contraction for “it is”) and “its” (the possessive form of “it”); the deeply annoying thing is that the rule is incredibly simple: if you can replace the word with the two words “it is,” and the sentence still makes sense, the right word is “it’s“; otherwise, “its.” No sentence diagram neeeded—just a little bit of English any first grader should know.