Study the table and explain the rule. read-reading, walk-walking, draw-drawing
write-writing, drive-driving, take-taking
chat-chatting, stop-stopping, plan-planning
occur-occurring, stir-stirring, refer-referring
lie-lying, die-dying, tie-tying
ski-skiing, taxi-taxiing
cry-crying, study-studying, play-playing
travel-travelling, cancel-cancelling,
control-controlling (BrE)

travel-traveling, cancel-canceling,
control-controling (AmE)