Or search: papilionoideae
2 Syllables: SU
burnished, churches, churlish, courage, curses, Curtis, earnest, Ernest, flourish, furnish, furtive, girlish, merges, nourish, nurses, perches, permits, purges, purplish, purses, scourges, searches, service, skirmish, surfaced, surges, Turkish, urges, verdicts, verses, worketh
3 Syllables: SUU
emerges
3 Syllables: USU
assertive, coercive, discourage, discursive, encourage, researches, reverses, subversive

Found 40 words across 3 groupings. Skipped 6 excess words of a similar stem.