英文關鍵字
activity
adult
background
blurred
busy
city
commuter
crowd
crowded
descend
down
elderly
escalator
female
group
heavy
helps
hurry
indoor
kindness
luggage
man
metro
moscow
motion
move
old
passengers
person
senior
silhouette
staircase
stairs
stairway
station
step
stress
subway
suitcase
traffic
transportation
travel
traveling
trolley
tube
tunnel
underground
unrecognizable
urban
walkway