"Zmniejszyli rozmiar systemu."

Translation: They decreased the size of the system.

[one_half_3544]

'they've lessened the size of the system'?

[Jellei]

Wouldn't "lessen" work in terms of amount of something, but not size?

[knoakes]

Although legal English I don't think I've ever heard "lessened" used in my 53 years of life. In this instance it would surely be reduced, decreased or maybe even downsized.

[KVRMx]

I agree. To me “lessened” should work here, too.

[SashaVolko1]

Czy mogę powiedzieć reduced zamiast decreased?

[Jellei]

Tak.

[ziggy69]

Why can't it be "We decreased the system size." ?

[Jellei]

"we" is the wrong pronoun, but ok for "system size", added.

[DerrickMcClure1]

That should be "They REDUCED the size of the system". "Decrease" is not a transitive verb.

[alik1989]

It's both transitive & intransitive according to Merriam-Webster:

https://www.merriam-webster.com/dictionary/decrease

[DerrickMcClure1]

I stand corrected, but it still sounds odd to me. Maybe a predominantly American usage.