GMC 1993 Safari Owner's Manual page 163

proceed with caution, yielding the right of way to pedestrians and sometimes
to other vehicles.
Some traffic lights also use red arrows to signify that you must stop before
turning on red.
Many city roads and expressways, and even bridges, use reversible-lane
traffic control during rush hours. A red X light above a lane means no driving
in that lane at that time. A green arrow means you may drive in that lane.
Look for the signs posted to warn drivers what hours and days these
systems are in effect.
H
REVERSIBLE
LANE ON
MULTI-LANE
ROADWAY
Pavement Markings
L
NO PASSING ZONE
AM40201 6
Pavement markings add to traffic signs and signals. They give information to
drivers without taking attention from the roadway. A solid yellow line on your
side of the road or lane means "don't cross."
Your Own Signals
Drivers signal to others, too. It's not only more polite, it's safer
to
let other
drivers know what you are doing. And in some places the law requires driver
signals.
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