When he spoke at the meeting, you would hear a pin drop.

等他一讲话， 会场鸦雀无声。

《新英汉大辞典》

Inside a bowling alley: Please be quiet, we need to hear a pin drop.

在保龄球馆：保持安静，我们需要倾听大头针落地。

youdao

So when you say you can "hear a pin drop," it means that the room is silent.

所以当你说你可以“听见针掉在地上的”，这意味着房间很安静。

youdao

"You could hear a pin drop, " says Charles Dockendorff, chief financial officer and another Tyco veteran.

FORBES: Magazine Article

You could hear a pin drop, and the typical friendly greetings were absent.

FORBES: What I Learned from Leaving the Safe Unlocked

But when you're in those blocks and the whole stadium is quiet, you can hear a pin drop, literally.

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