Here is a list of verbs that start with RI.
ricocheted, rid, ridden, ridding, riddled
riddling, ride, rides, ridicule, ridiculed
ridiculing, riding, riffle, rifled, rig
rigged, rigging, rimmed, ring, ringed
ringing, rings, rinse, rinsing, rioted
rioting, rip, ripened, ripening, ripped
ripping, ripple, rippled, rippling, rise
risen, rises, rising, risk, risked
risking, ritualized, rival, rivaled, rivalled
riven, rivets
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