ahead
alert
attention
background
barrier
beware
bump
bumpy
careful
caution
closeup
danger
direction
drive
europe
forbidden
halt
highway
hour
hump
isolated
limit
metal
metallic
obstacle
pole
red
road
roadside
roadsign
roadway
route
rule
safety
sign
signboard
signpost
slow
speed
street
traffic
transport
transportation
triangle
uneven
up
warning
way
white