You might be confusing the word it's with its. These words are commonly misused.

Pronunciation

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Contraction

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Contraction
it's

  1. A contraction of it is.
    Bring your coat. It's raining.
    "Where's the book?" "It's on the teacher's desk."
    "What's that?" "This? It's just a piece of paper."
  2. A contraction of it has.
    It's been a long time since I've had cake.
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