advice
alert
arrow
black
blank
car
caution
curve
decay
decompose
direction
directional
drive
guide
highway
icon
illustration
information
law
metal
nobody
old
one
post
putrefy
right
road
rot
rule
rust
safety
sign
signage
signpost
slow
steel
straight
street
symbol
traffic
transport
transportation
vehicle
warning
way
white
yellow