機器
background
black
cancellation
car
color
commemorative
culture
diminishing
drawing
engine
horizontal
illustration
in a row
isolated
lao
laos
laotian
locomotive
london
london tube
london underground
metro
nobody
paper
passenger
perforated
philatelic
photo
photograph
platform
postage
postage stamp
postmark
rail
railcar
railroad
row
rows
shot
stamp
station
studio
studio shot
subway
track
train
tube
tunnel
underground