Any number of pet peeves that annoy literate people. See also spelling pet peeves!
  • your vs you're
    You're likely to break your leg with that stunt.
    You're gracious to lend me your jacket.
    Again, no possessive pronoun has an apostrophe. Think (you'are).
  • then vs than
    She went to the store, then to the carwash. It was hotter than Hades at the sauna.
    Funny thing, programmers never spell if-then wrong, but many don't know that than is a word.
  • affect vs effect
    His speech affected the audience, and effected discussion in the legislature.
    She turned the knob without knowing what it would affect; she decided she liked the new effect.
    To 'affect' something is to change it somehow. An 'effect' is indirect: the results of a change.
  • irony vs juxtaposition
    It was ironic that Ted Kaczinski was so against technology, but was only found when his manifesto was published on the Internet.
    It was a coincidence that it was Ted Kaczinski's own brother who turned him in.
    The word 'irony' implies unexpected opposites; two things together that make you go 'hmm' is just a meaningful juxtaposition.
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