Semi-automatic refers to a type of gear transmission in an automobile. While a manual transmission requires the driver to change gears by hand while depressing a clutch pedal, and an automatic car performs both clutch and gear functions for the driver, a semi-automatic lies in between. It does not have a clutch pedal, but does require the driver to shift gears. In the UK, you can drive a semi-automatic car while holding either a manual or automatic licence.
Make sure that the gear lever in your car is in the "Neutral" position. It is usually signified by the letter "N." Press the brake pedal with your right foot and turn the ignition key to start the car.
Push the gear stick to the position labelled "1." This engages first gear. Most semi-automatic cars have a simple backward and forward stick to shift up and down the gears. This contrasts with the common "H" formation of gears on a manual transmission vehicle.
Release the handbrake and depress the accelerator pedal gently to pull away. Use your right foot for both the accelerator and brake pedals.
Increase speed and revs to change up to second gear. When at an appropriate speed, simply push the gear stick to the "2" position. As with a manual car, the revs should be appropriate for the speed you are going. This is a skill you learn before passing your driving test. As a general rule, the revs are correct if there is no jerk to the car when you shift gears.
Continue shifting gears up and down in response to traffic conditions. Like manual cars, semi-automatic cars may have four or five forward gears (and one reverse gear), with the higher the number suitable to higher speeds.
Put the gear stick back to the "N" position when you park. Engage the handbrake and turn the engine off.
Some semi-automatic vehicles have paddles either side of the steering wheel that the driver can use to change gear. This technology is derived from that used in racing cars. Typically the driver depresses the right-hand paddle to move up the gears, and the left-hand paddle to go down.