breaking a sweat

1. He's so smart he aces through all his exams without even breaking a sweat.
2. The other team wasn't very good; we won the game, and we didn't even break a sweat.
3. I used to be able to hike for hours without breaking a sweat; now, I get exhausted so easily.
4. Honestly, I broke a sweat when the cop told us to get out of the car.
5. Todd gets so nervous in social situations, whereas his twin brother, Tom, can work a room without breaking a sweat.

You can literally break a sweat when you feel warm and uncomfortable, and you start sweating. You can also figuratively break a sweat when you have a hard time doing something or when you look or feel uncomfortable. This idiom is often used in the negative using without or using a negative auxiliary verb (don't; doesn't; won't) to mean "have an easy time" or "not be uncomfortable".

vocabulary:

ace through - do very well; get good grades; get perfect scores

hike - walk for exercise or to see beautiful scenery (as in the mountains or in the country)
work a room - be social; greet people; network; mingle

literally - exactly

figuratively - metaphorically; symbolically

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