Walking, jogging or running but not in a vehicle or on the back of an animal(adverb)
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Use "by walking" in a sentence
"Throwing low-eighties fastballs, he halted any momentum he received from an easy first frame by walking A-Rod on four straight pitches."
"It was easy to eliminate them simply by walking the corridors; there were no strips of light showing under doors, no tell-tale humming and paper-shunting of photocopiers to be heard."
"In the bottom of the frame, Yankees hurler Roger Clemens retaliated with a high fastball at Boston outfielder Manny Ramirez, who took exception to the pitch by walking toward Clemens waving his bat in anger."