I have been pondering over this problem for quite a long time but still couldn't puzzle it out.

我想这个问题想了很久，但还是想不出答案。

youdao

Write a special message on the back of a puzzle or mail them one piece of a puzzle at a time.

在拼图的背面写上你特别的话，或者把拼图拆开每次寄给她一块。

youdao

You can do this by working on a puzzle, reading or spending time with friends and family.

你可以通过做做填字游戏，看看书，或把时间花在朋友家人身上来做到这些。

youdao

Last time we ended with the following puzzle or question.

上一讲结束时我们留下这个谜题。

耶鲁公开课 - 死亡课程节选

Any stealth game is a kind of real-time puzzle game with the option of brutal violence.

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One reason Mr. Pleskowicz and a new generation of Rubik's fanatics can solve the notoriously difficult puzzle in record time: They don't use Rubik's Cubes at all, instead substituting souped-up Chinese knockoffs engineered for speed.

WSJ: One Rubik's Cube, Many Knockoffs, Quintillions of Possibilities

Puzzle solving tools like warping time and making copies of yourself are better additions to gameplay.

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