神秘文句 - 拼圖

這是在網路上看到的，請勿咕狗，因為你一定會瞬間找到答案並自毀解謎樂趣。
想出來的人請勿透露答案，留給大家想。

題目：

This is an unusual paragraph. I'm curious how quickly you can find out what
is so unusual about it? It looks so plain that you would think nothing was
wrong with it! In fact, nothing is wrong with it! It is unusual though. Study
it, and think about it, but you still may not find anything odd. But if you
work at it a bit, you might find out! Try to do so without any coaching!

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有桌堪翻直須翻，莫待無桌後空翻

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