sweat/hard labor - metonymy

[Olympian]

Hello,

I came across the following definition of metonymy.

metonymy (miton'umē) [key], figure of speech in which an attribute of a thing or something closely related to it is substituted for the thing itself. Thus, “sweat” can mean “hard labor,” and “Capitol Hill” represents the U.S. Congress.

I can understand the use of "Capitol Hill" to mean "US Congress" (for example, I saw a headline like this: New changes on Capitol Hill leads to the largest freshman class for the House of Representatives in over half a century.)

But I don't know how to use "sweat" to mean "hard labor". Could you please give me an example?

Thank you.

[riquecohen]

But I don't know how to use "sweat" to mean "hard labor". Could you please give me an example?
.

He started as an office boy, but through his sweat rose to become the president of the company.

[acslater017]

"Finishing my thesis took a lot of time and a lot of sweat, but I did it!"

By the way, the phrases "sweat and tears" and "sweat and blood" mean lots of hard work, heartache, pain, sacrifice, etc.

[Olympian]

Thank you riquecohen and acslater017. Thanks for the information regarding those two phrases acslater017.