When writing, it is important to avoid repetitive language. One way to do this is by using synonyms for common phrases like "be founded on/upon." Some alternatives to this phrase include "rest on," "be based on," "depend on," "stem from," "originate from," "derive from," and "have its roots in." Each of these synonymous phrases accurately conveys the idea that something is built upon a particular foundation or source. Varying your language in this way can make your writing more interesting and engaging for your readers.