Or search: cert, surety, unsure, reliance, assurance, incertain, inevitability, overconfidence, predictability, indubitability, inevitableness, ineluctability, unavoidability, indisputability, unquestionability
3 Syllables: SUU
Burgundy, certainly, certainty, courtesies, currencies, currency, currently, fervently, Germany, Germany's, Hercules, nurseries, urgency, urgently
4 Syllables: SUUU
emergencies, emergency
4 Syllables: USUU
absurdities, concurrently, determinedly, fraternities, subserviency, uncertainly, uncertainties, uncertainty
5 Syllables: UUSUU
anniversaries, inadvertently, universities, University's

Found 28 words across 4 groupings.