When we talk about "broaden", we usually refer to expanding, extending, or widening something. However, it's always useful to have a few different synonyms at hand to diversify your vocabulary and express yourself more accurately. For instance, "enlarge" encompasses that same idea of expansion, while "diversify" conveys a sense of variation and multiplicity. "Extend" and "prolong" are also valid synonyms for a process of lengthening or stretching something out. "Amplify" and "augment" are more suitable when we want to emphasize the idea of increasing something in intensity or volume. Finally, "expand" and "spread" are both broad and versatile words to use in a variety of contexts when we need to convey the notion of growth or enlargement.