To add additional components to a previously constructed framework or device so that additional or improved functionality is obtained or created(verb)
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Use "build on" in a sentence
"But the opposition is determined to build on the uprising's strength."
"Once you reach boyfriend-girlfriend status, you start to build on what you already have confidence in."
"If you want to compile a sports library, it will be more onerous than before but similarly rewarding, particularly if you start with Hopcraft and build on his foundations."