It's simple! :) All you have to do is ask a question and the other player must answer Yes or No!
Example:
Person1: Do you own a pet?
Person2: Yes. Have you ever been to Sweden?
Person3: No. Do you take milk in your tea?
I will start us off!
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Have you ever forgotten your own birthday?
Example:
Person1: Do you own a pet?
Person2: Yes. Have you ever been to Sweden?
Person3: No. Do you take milk in your tea?
I will start us off!
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Have you ever forgotten your own birthday?