It's difficult to keep quiet sometimes because you might be a little nervous.

有时候很难保持安静，因为这时候的你有点紧张。

youdao

People sometimes say I’m aloof, quiet, and calm – and hard to get to know.

人们有时会说我很冷淡，不爱说话，还有总是很平静 ---难以捉摸

youdao

Rafe gets all my time and attention when I'm not travelling, but when I'm away he sometimes goes noticeably quiet.

当我不旅行的时候，我把所有时间和注意力都给了Rafe，但当我离开的时候，他有时显得异常安静。

youdao

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

And so we salute you for your gracefulness and your quiet heroism and sometimes not so quiet heroism.

CENTERFORSECURITYPOLICY: Monica Crowley, Mightier Pen 2012

Cromer successfully creates a Chekhovian atmosphere with Nelson's script, with some characters reminiscing out loud while others experience quiet, sometimes rueful epiphanies.

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In the end, nearly every major or minor crew member is given their quiet (or sometimes loud) moment with Shepard.

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