Soldiers have been training at a secret location.

士兵们一直在一个秘密的地方训练。

《柯林斯英汉双解大词典》

Rogue soldiers have operated with impunity, partly because investigations against them are run by secret military tribunals even when the alleged crime is against a civilian.

即使受到平民指控罪行时，作案士兵仍旧有罪不罚，很大原因是唯秘密军事法庭执有调查权。

youdao

But before the full horror could have set in, he would have been grabbed by the arms of two strong Russian soldiers wearing the uniform of the Soviet secret.

但在开始真正害怕之前，他们已经被两名穿着苏维埃机密制服的强壮的俄国士兵押住双臂。

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The Guernsey Literary and Potato Peel Pie Society came into being because of a roast pig we had to keep secret from the German soldiers, so I feel a kinship to Mr. Lamb.

NPR: Part One

It was a secret - top secret military technology that kind of allowed soldiers to have translations of languages in places like Afghanistan.

NPR: Report: Iran Halted Nuclear Ambitions

In the three earlier films, Matt Damon plays Jason Bourne, star of a top-secret CIA program that trains super-soldiers to carry out assassinations.

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