Judging from the amount of manuscripts I've seen where characters don't ever use contractions, everyone else must have had the same English teachers I did. Mine drilled into us in school the evils of contractions. Using contractions in a paper, even a fiction project, was enough to give them fits.
I did not enjoy high school English, in case you were wondering.
I'm here to tell you the honest truth. Your English teachers were wrong.
Sure, if you're writing professional papers, you want to use more formal language. But in fiction, uncontracted words are generally more distracting than contracted ones; they jolt a reader out of the flow of the reading experience. Especially in dialogue. For the love of all you hold dear, please use contractions in your dialogue. If contractions suit the time period and the style of the character you're writing, then use them. It's how most English-speakers talk.
(PS: I know there are elision-type contractions in many Romance languages at least; I'm curious if writers working in those languages run across the same issues, or if contractions are more accepted in non-English literature? Feel free to chime in below if you've got experience to share.)
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