What are the signs of an introvert female, if they like or dislike a person?

Are there any signs to look for if an introverted female likes or dislikes a person who has a crush on an introverted female and do not want the guy to approach them?
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+1 y
Especially, if they have never spoken or didn't get the chance to speak yet, due to busy work place?
What are the signs of an introvert female, if they like or dislike a person?
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