The students work in pairs.

Person 1 thinks about a person or a thing.
Person 2 asks questions and tries to find out what person 1 is thinking about. Person 1 is only allowed to answer yes or no.

Example:

Person 1: OK let's start. I'm ready!
Person 2: Is it a boy?
Person 1: No
Person 2: Is it a girl?
Person 1: Yes
Person 2: Is she a singer?
Person 1: Yes
Person 2: Is she over 50 years old?
Person 1: No

And so on....

Stop after 25 questions or stop when person 2 has guessed right answer!

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