The secret was not discovered until he was dead.

直到他死后这个秘密才被人发现。

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I discovered that a touch of corn syrup was the secret to creating a glossy, dark chocolate top.

我发现一丁点儿的玉米糖浆是创造出光滑黑巧克力顶层的秘诀。

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The staff at the home kept her secret for quite sometime, even after they discovered that she was a woman.

甚至，军人之家的工作人员发现她是女人后，很长时间内，继续保守这个秘密。

youdao

Tomlinson, who carried this developing fluid disguised as a bottle of Ralph Lauren toilet water, claims the technique was discovered by accident when a secret message from Russia was being decoded in the 1980s.

BBC: Spy tactics revealed by book

At the time Deutch left the agency in late 1996, CIA security officials discovered top secret documents on Deutch's home computer, which was a violation of strict CIA policy.

CNN: Former CIA director to serve on spy panel