The idiom for this week is “to not hold one’s breath”. It is used when we want to say that someone should not wait for something to happen when we know that it will never happen. For example:
The prime minister promised he would lower taxes this year, but I won’t hold my breath. Politicians always say things like that just to get elected.
A: Do you think the boss will give me a raise this year?
B: Don’t hold your breath! He never gives anyone a raise.
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A: Ned said he’d help me move this weekend.
B: If I were you, I wouldn’t hold my breath. He always says he’ll help people, but he never does it.
So, we often use this expression in the future tense (I won’t hold my breath.) or in the conditional tense (If I were you, I wouldn’t hold my breath.) However, the most common way of using it is in the imperative tense (Don’t hold your breath!) When it is used this way, it’s a little strong, but it’s not rude.
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