They used elaborate secret codes, as when the names of trees stood for letters.

他们用的是精心设计的密码，用树木的名称代表字母。

《柯林斯英汉双解大词典》

Many people enjoy secret codes.

许多人喜欢密码。

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Any realities in our hands are just secret codes for the grasp of our future.

许多我们把握在手的现实，只是未来把握我们的密码。

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He tipped the traders on UBS analyst recommendation upgrades or downgrades, using secret codes sent on disposable cellphones.

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Among other things, the principles established by his scholarship enabled espionage agencies to make their secret codes even more impenetrable and enhanced the security and accuracy of computer data transmission.

ECONOMIST: Andr�� Weil

This ability would allow a quantum computer to do the mathematical heavy-lifting required for, say, cracking secret codes, while even the fastest and most advanced supercomputers plod along on the same problem.

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