具体指脚时或英尺时的复数，就用feet如How many feet do you have I have two.He is 6 feet tall.foot：用在短语中或构成一些词：如on foot步行，也可用with feet（但不是步行，而是用脚的意思），但不用with foot的football；footprint脚印如I often go home on foot.Punching with fists and kicking with feet are allowed in taekwondo.跆拳道允许用拳击和用脚踢。