Note, in this case, do not take very deep breath, but hold your breath.

注意，这个情况下，不要做很深的呼吸，但是屏住呼吸。

youdao

She said she'd do it this week, but don't hold your breath!

她说她这个星期要干，不过你可别因此眼巴巴干等！

《牛津词典》

But do not hold your breath.

但不要屏住呼吸哦。

youdao

But, hold your breath come June 1 that the stimulus from QE2 will be enough to keep the economy growing and employment gaining.

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