GMC safari 2001 用户手册

There is a lever located on the inside of the seat to adjust
the seatback.

You can adjust the seatback
by lifting the lever and
leaning back. Release the
lever to lock the seatback
where you want it. Pull up
on the lever, lean forward
and the seat will go to an
upright position.

But don’t have a seatback reclined if your vehicle is moving.