Focus on the pronunciation of build (sth) on sth
English definition of “build (sth) on sth”
build (sth) on sth — Phrasal Verb with build
/bɪld/ verb (built, built)
› [T] to develop something that was started in the past or created by someone else: The study builds on research by the nation's leading geneticists. She built her success on years of experience in the fashion industry.