英文關鍵字
alarm
alert
attention
barricade
barrier
beware
blink
building
car
careful
caution
city
construction
danger
dangerous
detour
evening
flash
forbidden
hazard
illumination
industrial
labor
lamp
light
many
night
off
orange
redirection
riding
risk
road
roadsign
roadwork
safe
safety
sign
signal
stop
street
symbol
temporary
traffic
transport
transportation
warn
work
yellow