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ordinary; common; usual
free of charge
unaffected; as is; safe
only; merely; just; simply
but; however; nevertheless
「徒」 has other readings with different meanings.
駅まで徒歩で十分くらいかな。
It's about ten minutes on foot to the station.
徒歩で行くには遠すぎるよね。
It's too far to go on foot.
徒労に終わらないといいけど。
I hope it doesn't end in vain.