Keep reading to find out what they are.
1) Small Talk
Start scenes with the conversation already begun. End them as soon as that scene has moved the story where it needs to go.
But you can’t write a script entirely without exposition. There is some information that the audience needs to know. So you have to work to communicate that information in an interesting and natural way.
For instance, instead of having characters discuss that it’s New Year’s Eve, have them exchange resolutions. Then the audience knows the situation without having to be told outright.
Monologues slow scripts down, and they rarely (if ever) happen in real life.
Plus, if you have a bunch of monologues in your story, each successive one will carry less weight, so that one great monologue in the third act won’t seem nearly as momentous as it should.
4) No Rhythm
Not only should every character have their own voice, the rhythms of their conversations should change depending on who they are talking to.
The rhythm of a Jerry and George conversation is different from that of Jerry and Elaine, which is way different than Jerry and Kramer. You get the point.
6) Throat Clearing
These are phrases you probably don’t need, so use them sparingly. They are just an example of you (the writer) clearing your throat on the page.
And writing a character that says ‘listen’ or ‘you know’ constantly, as part of their character, isn’t nearly as unique and special as it might at first seem. There are better ways to differentiate the way people talk.
7) Inauthentic Reactions
That means they need to have honest reactions to information they are given. If someone learns their loved one just died, they aren’t going to say something witty, they’re going to react in the moment.
Write honest moments, and don’t be pre-occupied with writing smart or witty retorts all the time, and your dialogue will be much more effective.
8) Too Long
It can be hard not to repeat yourself in dialogue, but this is really just another example of the writer clearing their throat.
“I hate John! John’s an asshole! John can’t come back here anymore!”
Pick one and move on.
9) No Subtext
People are way more difficult to read than that. We don’t say what we mean. We manipulate people or lie or deflect, secretly hoping to get what we want. So your characters should do that too.
10) Everyone Sounds the Same
That has some merit, sure.
But honestly, you should be able to tell by the content just as easily as by the way they talk. Lots of times what people say communicates character just as much as how they say it. (What they do communicates character better than anything else, but that's a different article.)
If you cut me in line at the bank, I’m gonna say “HEY WTF!?” and Chelsea is going to say “Go right ahead.”
So make sure you always keep your character’s perspective and who they are in the front of your mind, just as much as you consider how they talk, always remember it’s what they say that will really set them apart.
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