An example of a knowledgeable person is a quantum physics expert.
Having mastered the knowledge to become a London black cab driver, Serek is now becoming knowledgeable about the overseas property market.
The head teacher was knowledgeable in each subject.
I have always found Emma Ginn to be immensely knowledgeable and helpful.
They were each knowledgeable in their particular field.
He was a knowledgeable chap.