Very good! But you need a question mark after SWIM to make it clear that a question follows this phrase.
Поднимите руки
(Let's have/By a) show of hands
Example
Поднимите руки (те), кто умеет плавать
Example translation
(Let's have a) show of hands, who can swim
Translator's comment
(a) show of hands также обозначает голосование (поднятием рук)
в разговорной речи часто употребляется в сокращенном варианте: "Show of hands... How many people remember George Carlin's 'Seven Words You Can Never Say on Television'?"
Discussion (7)
(Let's have a) show of hands — who here knows how to swim?
Uly, forgive me, but I am not going to re-add this once again. Let's say the question mark is missing by mistake
👍🏼
It’s not just the question mark. it’s the punctuation and the formulation of the question. It looks more like a statement about hands that know how to swim. I corrected it for you in the comment above.
Don't worry, I added my own translation of this, which I think makes everything clearer.