How to say in Czech: How good is their Polish?

English
How good is
Czech
Jak dobře umějí polsky?
Their Polish is getting better.
Their Polish is very good.
How do you say that in Polish?
I do not speak Polish very well.
You speak Polish very well.
Their native language is Polish.
Are they learning Polish on their own?
He is learning Polish.
He is not Polish.
He is Polish.

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