Or search: swear, commit, devote, engage, pledge, plight, profess, betroth, dedicate, affiance, assurance, consecrate
2 Syllables: SU
bowing, Browning, browsing, crouching, crowding, crowning, Dauphin, doubting, Downing, drowning, fowling, frowning, housing, howling, mowing, outing, ploughing, plowing, prowling, rousing, routing, scouting, scowling, shouting, spouting, sprouting, towering
3 Syllables: USU
accounting, allowing, amounting, arousing, avowing, endowing, espousing
4 Syllables: UUSU
overpowering

Found 35 words across 3 groupings.