on foot

步行

on a weekly (daily basis), on account of, on an average, on an even keel, on and off, on average, on balance, on behalf of, on board, on business, on condition that, on credit, on cue, on diet, on display, on duty, on earth, on end, on file, on fire, on guard, on hand, on instalments, on instinct, on no account, on occasion, on one's guard, on one's head, on one's honor, on one's honour, on one's own, on one's way to..., on order that, on principle, on purpose, on relief, on sale, on schedule, on second thoughts, on the alert,