For the simple reason that the number of possible chess games is so huge, that computers can't calculate it.

原因很简单,棋局的潜在变数相当之大,以至于计算机根本无法将其完全计算出来

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However, there's one other variable that you want to be aware of and that is, he knows he ought to be going straight ahead like that, but he also knows that his right flank is open.

然而,还有其他变数是必须考虑到的,那就是,士兵知道他是向前直行的,但是,他同样知道他的右路是洞开的

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