2 Syllables: SU
buttoned, Drummond, flooded, hubbub, hunted, roughened, rugged, rusted, Rutland, summoned, upland
2 Syllables: US
beloved
3 Syllables: USU
accustomed, consulted, disgusted, distrusted, encouraged, resulted, rivulets
4 Syllables: UUSU
unaccustomed

Found 20 words across 4 groupings. Skipped 1 excess word of a similar stem.