foolish / stupid / expressionless / blank / to stay
呆
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口
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木
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The fool wants to make fun of Don Quixote in front of the airplane. To fool him, he set up a Christmas tree to look like a huge animal by putting a mandarin on top which looks like the head of the animal. Don Quixote thinks he met his arch enemy and starts to charge the construction, much to the fool's delight.