dobrze znać się na czymś in inglese:

Being knowledgeable about Japanese culture is a good thing.

Tom is very knowledgeable about Japanese art.

Tom is quite knowledgeable about modern popular music.

He's very knowledgeable about art.

to be knowledgeable about sth

He had never come across anyone more knowledgeable than himself.

Mathematics are usually knowledgeable people.

Malcolm is knowledgeable about computer hardware and will tell you everything you want to know.

Graham’s very knowledgeable about wines.

The head teacher was knowledgeable in each subject.

A good doctor has to be knowledgeable and sensitive.

Dr. Smith is the most knowledgeable expert in that subject.

Traveling makes people knowledgeable.

Truthful speech is not elegant, and elegant speech is not truthful. Good words are not persuasive, and persuasive words are not good. The knowledgeable are not many, and the many are not knowledgeable.