From Longman Dictionary of Contemporary Englishbe in good/fine/great etc formbe in good/fine/great etc form (also be on good/fine/great etc form British English)GOOD AT to be full of confidence and energy, so that you do something well or talk in an interesting or amusing way Michelle was in great form at last week’s conference. → form
Examples from the Corpus
be in good/fine/great etc form• Davies, now in his 80s, is in fine form.• That is our strength and our forwards are in good form at the moment.• At least he is in good form again.• I was in good form that night.• Fortunately, Alan Judge was in fine form, pulling off a great save to keep Hereford in the game.• Office manager is on holiday this week., and assistant manager are in good form.• Health Management Associates Inc., known as the Wal-Mart of hospital operators, appears to be in fine form. 