Exam is like sex

After I left examination room last week, an idea came into my mind. When I told it to my coursemates they laughed more than I would have expected. So, maybe its not that bad idea, and I can put it here for your evaluation:

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Exam is like sex. After you finish an exam, you sort of feel, how well you did: "Yeah, OK" or "I truly don't know" or "It was great". But at the end you are never the only one, who evaluates how well you did on the exam.
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