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In Honor of National Grammar Day, Here Are the Worst Grammar Mistakes You Can Make

In Honor of National Grammar Day, Here Are the Worst Grammar Mistakes You Can Make

Today is National Grammar Day, and I aim to celebrate! (Fun fact: it's held on March 4th because March 4th is also an imperative: march forth.) I happen to love grammar; even the silly little rules that exist for no reason bring me a strange amount of glee. But I also love grammar mistakes, in a ruthless, Professor McGonagall sort of way. In honor of National Grammar Day, here are seven of the worst ones out there (and how to avoid them):

  1. Which, that, and who. "Which" and "that" are similar enough that I can understand them. "Which" introduces relative clauses like I tickled your little brother to death, which you would know if you looked behind you. "That" is a restrictive pronoun, as in I wouldn't have done it if he hadn't dangled that participle. But how do you get "who" mixed up with those? "Who" is the only one that can be used for people, as in It's not like you don't have other siblings who are much better at grammar. Please, never use "that" or "which" to refer to a person, okay? We're not even going to get into the "who" vs. "whom" thing.
  2. Your and you're. Come on. This isn't that hard. "Your" is a possessive pronoun, as in Your sister is much better at identifying dangling participles than your brother was. "You're" is a contraction of "You" and "are," as in You're not going to cry that he's dead, are you?
  3. There, they're, and their. "There" refers to a location, for instance: I think I'll put his body over there. "They're" is a contraction, as in They're never going to find it! And "their" is a possessive pronoun, as in Their tears will dry once they see the spelling mistakes in his last essay.
  4. Affect and effect. This one's confusing, but once you learn the difference, you (like me) will be very annoyed when people consistently misuse them. "Affect" is a verb. (How can the loss of such a poor grammarian affect you like this?) "Effect" is a noun. (If I had known it would have such a strong effect on you, I might have spared him.)
  5. "Could of." This one drives me nuts, mostly because it makes no sense. "Could of" is a mispronunciation (and spelling) of "could've," as in "could have." I'm not exactly sure what use "could of" has in a sentence.
  6. Putting punctuation outside quotation marks. Unless you're British, this is a mistake. Punctuation should almost always go inside your quotes.
  7. Not capitalizing "I." This isn't so much a grammar mistake so much as it is poor taste. If you're writing anything, please do the world a favor and take the two extra seconds to refer to yourself as "I" and not "i." Editors everywhere will thank you.

What's your grammar pet peeve?

Topics: Life
Tags: grammar, holidays, punctuation, weird holidays, national grammar day

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About the Author
Jennifer Grudziecki

Jennifer Grudziecki is a writer, intern, and soon-to-be college graduate living in New York City. Her life goal is to be a space pirate, and maybe to write a book along the way. Follow her on Twitter @JennyGrudzy or on Tumblr at

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