He took a long slow breath, inhaling deeply.

他缓缓地深吸了一口气。

《柯林斯英汉双解大词典》

So take a deep, slow breath.

现在，做一下深呼吸。

youdao

Take a deep, slow breath, taking in as much air as you can as slowly as you can.

深深地，慢慢地呼吸，尽量慢，尽量吸入更多的空气。

youdao

Again, deep breath in; slow, gentle, quiet breath out.

再一次深深吸气;,缓慢，平稳，安静地呼气。

哈佛公开课 - 幸福课课程节选

When faced with tough questions like these, take a deep breath, slow down, and then sound out your thinking process aloud, and walk the interviewer through how you get to an answer.

FORBES: The Most Oddball Interview Questions of the Year