The fire-fighters stand and watch for the first time in days.

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What is the meaning of 'in days'? what other expressions can use instead of 'in days'? Thank you.

It sounds as if the firefighters had been working for many days, fighting a particularly bad fire ... and after all those days, are finally able to relax a bit and just watch.

The phrase "in days" implies they've been working hard for several previous days.