They left under the cloak of darkness.

他们在黑暗的掩护下离开了。

《牛津词典》

Undeterred, he crept into the cemetery under the cloak of darkness with a bemused sculptor in tow.

他没有被吓住，在黑暗的掩护下，拖着一个困惑的雕刻家，蹑手蹑脚地走进墓地。

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Undeterred, he crept into the cemetery under cloak of darkness with a bemused sculptor in tow.

丹东并未就此罢休，借着夜色的掩护，他拖着一位困惑的雕刻家潜入墓地。

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Apparently that actually happened, sometimes under the cloak of darkness, resulting in pressure on the home-course super to goose up speeds by whatever means necessary, even if that meant scalping the greens or taking other measures likely to cause long-term damage.

WSJ: Ta-Da! The USGA Gives the Stimpmeter a Makeover | Golf Journal by John Paul Newport