It's always the quiet ones.

那些安静不语的人总是能达到这样的效果。

youdao

The quiet ones always sneak up on you.

有些人总是不鸣则已一鸣惊人。

youdao

These are the ones who haven't bothered to divorce, yet they lead lives of quiet, grinding frustration, if not desperation, hostility, anger and depression.

如果不是绝望、敌意、愤怒和沮丧就好了，这些夫妻也不会自寻烦恼，选择离婚，而是会选择一种安静的，互相消磨的生活方式。

youdao

The famous saying, 'It's the quiet ones you need to watch, ' definitely applies to this style.

WSJ: Stealing Style From Granny

We know each other so well as a team, the quiet ones were left to their own devices on the coach on the way to the Millennium Stadium, while us louder ones were lapping it all up.

BBC: SPORT | Rugby Union | Six Nations | Don't stop celebrations - Thomas

The conversation moved on to those intense days of war almost 15 years back and we did what any member of the journalist tribe does when gathering after many years apart - slagging off the louder mutual acquaintances and wondering what ever happened to the quiet ones.

BBC: A classic tale of a life made good in America