The Cassette Recorder
Two guards were on duty outside a barracks. One faced up the road to watch for anyone approaching from the North. The other looked down the road to see if anyone approached from the South.
Suddenly one of them said to the other, “Why are you smiling?”
How did he know his companion was smiling?
Ah! Click here to read the solution.
They were facing each other. As to why his companion was smiling, the world may never know.
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