Chevrolet 2003 Cavalier Owner's Manual page 31

Lap-Shoulder Belt
All rear seating positions have lap-shoulder belts. Here's
how to wear one properly.
1. Pick up the latch plate and pull the belt across you.
Don't let it get twisted.
The shoulder belt may lock if you pull the belt
across you very quickly. If this happens, let the belt
go back slightly to unlock it. Then pull the belt
across you more slowly.
2.
Push the latch plate into the buckle until it clicks.
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