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2 Syllables: SU
abo, aro, Austro, auto, borrow, Bravo, Caro, follow, grotto, hollow, lago, Malo, morrow, Moscow, motto, mottoes, Otto, Paulo, Roscoe, sorrow, Stockholm, Strabo, swallow, topmost, wallow
3 Syllables: USU
4 Syllables: UUSU

Found 40 words across 3 groupings.