機器
catastrophe
caution
command
crash
crisscrossing
cross
crossing
danger
death
engineering
gambling
industry
infrastructure
injunction
instruction
intersection
landmark
landscape
level
life
mark
misfortune
mishap
notice
order
outdoors
passage
poland
rail
railway
red
regulations
road
safety
sign
stop
street
symbol
traffic
trail
train
transit
transport
travel
unguarded
vehicle
warning
way
work