izpopolníti to improve, to make perfect; to ameliorate, to make better; to perfect (svojo francoščino one's French); to bring to perfection
izpopolníti komisijo to complete a board
izpopolníti kakovost to improve the quality
izpopolníti nedostatke to make up deficiencies (ali shortages)
izpopolníti se to make oneself (ali to become) more proficient (ali more skilful (v čem in something)), to reach perfection
izpopolníti se v angleščini to perfect one's English