英文關鍵字
alarm
alert
ambulance
attention
auto
automobile
beacon
blue
car
control
cop
crime
criminal
danger
emergency
enforcement
firemen
flash
flasher
glass
glint
industrial
justice
lamp
law
light
patrol
police
protect
protection
red
revolving
road
roof
rotating
row
security
service
several
sign
signal
siren
street
support
surveillance
traffic
transportation
urgency
vehicle
white