英文關鍵字
adolescent
athlete
athletic
blue
boy
cardio
caucasian
champion
confident
dangerous
development
equipment
extreme
fun
gathering
health
helmet
hobby
kids
kneecaps
leisure
lifestyle
momentum
outdoor
park
people
practice
protection
ramp
recreation
roller
rollerblade
schoolboy
skating
skill
speed
sports
sportsman
strength
summer
training
trick
yellow
young