The audience was so quiet you could have heard a pin drop.

观众安静得连针落地的声音也听得见。

《牛津词典》

That was why the place was so quiet.

这就是这个地方如此安静的原因。

youdao

How strange it is that the students are so quiet in the classroom!

真奇怪，学生们在教室里那么安静！

youdao

And again, Americans all around the country took note of this quiet,serious man who did such effective work in so many different kinds of situations.

VOA: special.2011.02.10

And that's how it actually gets to be so quiet when you have on, supposedly, these quite expensive headphones.

所以你戴上它后会觉得,周围非常安静，可想而知,这种耳机非常贵的。

麻省理工公开课 - 化学原理课程节选

but it's important to get some peace and quiet sometimes, so I do go to Central Park for that.

但有时候得到一些平静和安宁也很重要，这种时候我就会去中央公园。

街上的售票员 - SpeakingMax英语口语达人

Still, it's not surprising that it's been so quiet here, says political analyst John Ralston.

NPR: Candidates Snub Nevada, Despite Earlier Caucus

Which makes me wonder, what is the real reason Sony is being so quiet?

NPR: Sony's Secretive 'Da Vinci Code' Marketing Plan

Fifteen minutes later, the plane took off and I glanced back to see why it was so quiet.

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