Or search: renewable, unfailing, unlimited
3 Syllables: SUU
audible, doggerel, laudable, nautical, nominal, plausible, possible, probable, topical, volatile
4 Syllables: USUU
abdominal, apocryphal, canonical, impossible, improbable, inaudible, inaugural, methodical, phenomenal
6 Syllables: UUUSUU
anthropological, etymological

Found 21 words across 3 groupings.