3 Syllables: SUU
musically, nudity, unity, uselessly
4 Syllables: USUU
annuity, community, conclusively, confusedly, exclusively, gratuity, immunity, impunity
5 Syllables: UUSUU
assiduity, contiguity, importunity, incongruity, incredulity, perpetuity, perspicuity, superfluity, unobtrusively
6 Syllables: UUUSUU
discontinuity

Found 22 words across 4 groupings.