Here is a list of verbs that start with RU.
rub, rubbed, rubberized, rubbing, ruffled
ruffles, ruin, ruined, ruining, rule
ruled, rules, ruling, rumbled, rumbles
rumbling, rummaged, rummaging, rumored, rumpled
run, runaway, rung, runing, running
runs, ruptured, rush, rushed, rushes
rushing, rust, rusted, rustle, rustled
rustling, rutted
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