There are several synonyms for the phrase "adding to", which can be used to convey similar meanings in different contexts. These include "contributing to", "enhancing", "increasing", "amplifying", "augmenting", "building upon", "supplementing", "expanding", "enriching", "strengthening", "fortifying", "cementing", "consolidating", and "bolstering". Each of these synonyms has a slightly different connotation, but they all imply the idea of making something greater or more comprehensive by adding to it. Whether you are writing an essay, a business proposal, or simply communicating with others, using synonyms can help you avoid repetition and add variety to your language.