When you're writing a sales letter, use the same language that you would use when you're talking to someone face to face.
Instead of saying "You are right," say "you're right." Instead of using "You will" use "You'll."
Contractions keep the copy smooth and easy to read. Your advertising, sales letters will be easier to read because the reader is going through the copy as thought they are speaking. Take note next time you're reading. You'll notice how much easier it is to read You'll as opposed to You Will
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