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QuizTraffic rulesMexico

Test your knowledge with our multiple-choice quiz. Learn from each answer and improve your understanding of the traffic rules and road signs of Mexico.

For informational purposes only. Always follow official regulations. Some content and images were created with AI assistance.

Traffic signs
Traffic rules
Mexico
True/false 17 Mexico 14 Car controls 109 Dashboard lights 40 Priority rules 9 Pedestrians 19 Cyclists 20 Show all 581
What should you check after fitting a wheel?

451. What should you check after fitting a wheel?

That the wheel can move slightly on the hub.
That the wheel nuts are covered by the trim.
✓ That the wheel nuts are tightened correctly.
That the jack remains partly under the vehicle.

After fitting a wheel, make sure the wheel nuts are tightened correctly using the manufacturer's specified procedure and torque. Incorrectly tightened wheel nuts can loosen or damage the wheel. Recheck them later if the vehicle or wheel manufacturer recommends it.

Checking wheel nuts after fitting a wheel
AI-generated by Rijbewijs-online.be • WCIT • CC BY-SA
What may happen when you press the accelerator fully in an automatic vehicle?

452. What may happen when you press the accelerator fully in an automatic vehicle?

The parking brake applies automatically.
The transmission selects Park.
✓ The transmission may shift to a lower gear for stronger acceleration.
The engine switches off.

In many automatic vehicles, pressing the accelerator fully can activate kickdown, causing the transmission to select a lower gear and provide stronger acceleration.

Accelerator-pedal operation for automatic kickdown
AI-generated by Rijbewijs-online.be • WCIT • CC BY-SA
What does this dashboard symbol indicate?

453. What does this dashboard symbol indicate?

Windscreen washer.
Air conditioning.
✓ Rear window demister.
Front windscreen demister.

This symbol indicates the rear window demister. It heats the rear window to help clear condensation, mist or frost and improve visibility.

Rear-window demister symbol on the dashboard
AI-generated by Rijbewijs-online.be • WCIT • CC BY-SA
What does this vehicle-control symbol indicate?

454. What does this vehicle-control symbol indicate?

✓ Air conditioning.
Rear window demister.
Fan speed.
Air recirculation.

The A/C symbol controls the vehicle's air-conditioning system. Air conditioning can cool and dehumidify the air inside the vehicle, which can also help clear mist from the windows.

Air-conditioning control with the A/C symbol
AI-generated by Rijbewijs-online.be • WCIT • CC BY-SA
How should luggage or other cargo be carried in or on a vehicle?

455. How should luggage or other cargo be carried in or on a vehicle?

Where it is easiest to reach while driving.
Anywhere, as long as the vehicle is not overloaded.
✓ Securely, within load limits, without blocking visibility or lights.
Loosely in the boot so it can move a little.

Unsecured or overloaded cargo can affect steering and braking, injure occupants during sudden stops, or fall into the road. It must not obstruct the driver's view or vehicle lights.

Luggage and cargo carried in a vehicle
AI-generated by Rijbewijs-online.be • WCIT • CC BY-SA
Why should you leave a safe following distance inside a tunnel?

456. Why should you leave a safe following distance inside a tunnel?

✓ You need enough space to react if traffic slows or stops.
To make it easier for other vehicles to overtake.
Because tunnels usually have a poor road surface.
To prevent your headlights from overheating.

Limited space and visibility can make incidents inside tunnels especially dangerous. A safe gap gives you more time to react.

Gap between vehicles travelling through a tunnel
AI-generated by Rijbewijs-online.be • WCIT • CC BY-SA
What should you do if the windscreen wipers leave the glass smeared?

457. What should you do if the windscreen wipers leave the glass smeared?

Apply lubricant to the wiper blades.
Ignore it unless the wipers stop moving.
Replace the washer pump instead of the blades.
✓ Clean the windscreen and blades, and replace worn blades.

Worn or dirty wiper blades can seriously reduce visibility in rain. Clean them first and replace them if they remain ineffective or damaged.

Wiper streaks on a vehicle's windscreen
AI-generated by Rijbewijs-online.be • WCIT • CC BY-SA
You may drive through an amber light without slowing down.

458. You may drive through an amber light without slowing down.

True.
✓ False.

An amber light means you should stop if you can do so safely. If you are too close to stop safely, continue through the junction with caution.

Vehicle approaching an amber traffic light
AI-generated by Rijbewijs-online.be • WCIT • CC BY-SA
Why should you be careful when turning across oncoming traffic?

459. Why should you be careful when turning across oncoming traffic?

Turning makes your vehicle take longer to accelerate.
Your steering becomes less responsive during the turn.
Oncoming vehicles need more distance to change lanes.
✓ You must judge the speed and distance of approaching vehicles.

Turning across traffic requires careful observation. Misjudging speed or distance can lead to a serious collision.

Vehicle preparing to turn across oncoming traffic
AI-generated by Rijbewijs-online.be • WCIT • CC BY-SA
What does this dashboard symbol indicate?

460. What does this dashboard symbol indicate?

Brake-system fault.
ABS fault.
Low tyre pressure.
✓ Brake-pad wear warning.

This symbol indicates that the brake pads may be worn and should be inspected. Continuing to drive with excessively worn brake pads can reduce braking performance and damage other brake components.

Brake-pad wear warning symbol on the dashboard
AI-generated by Rijbewijs-online.be • WCIT • CC BY-SA
What should you expect if the engine suddenly stalls while the vehicle is moving?

461. What should you expect if the engine suddenly stalls while the vehicle is moving?

The steering and brakes will stop working completely.
✓ Steering and braking may require more effort, so move to a safe place.
Power assistance will continue working normally.
The vehicle will stop immediately when the engine stops.

Power assistance may be reduced when the engine stops. Keep control, use the hazard lights if needed, and steer toward a safe stopping area.

Driver responding to an engine stall while moving
AI-generated by Rijbewijs-online.be • WCIT • CC BY-SA
How should you use the brake pedal during emergency braking in a vehicle with ABS?

462. How should you use the brake pedal during emergency braking in a vehicle with ABS?

✓ Press it firmly and keep it pressed.
Release it if the pedal vibrates.
Use the parking brake instead.
Pump it rapidly.

During emergency braking with ABS, press the brake pedal firmly and keep it pressed. Pulsation or vibration through the pedal can be normal while ABS is operating, so do not pump or release the brake.

Firm brake-pedal pressure during emergency braking with ABS
AI-generated by Rijbewijs-online.be • WCIT • CC BY-SA
What should a motorcyclist do in strong crosswinds?

463. What should a motorcyclist do in strong crosswinds?

✓ Reduce speed and be prepared for sudden gusts.
Follow a large vehicle closely for protection from the wind.
Make sudden steering movements whenever the wind changes.
Accelerate to get through the windy area quickly.

Strong crosswinds can push a motorcycle sideways and sudden gusts can affect its stability. Reduce speed, keep a steady grip on the handlebars and allow extra space, especially on exposed roads, bridges, or when passing gaps and large vehicles.

Motorcyclist riding in strong crosswinds
AI-generated by Rijbewijs-online.be • WCIT • CC BY-SA
You should always wear a seat belt, even on short trips.

464. You should always wear a seat belt, even on short trips.

False.
✓ True.

Seat belts reduce the risk of serious injury and should be worn on every trip, even short ones.

Driver wearing a seat belt for a car journey
AI-generated by Rijbewijs-online.be • WCIT • CC BY-SA
Why should you use headlights in poor visibility?

465. Why should you use headlights in poor visibility?

To keep the windscreen clear.
To make the brakes respond faster.
To prevent the tyres from slipping.
✓ To see better and be seen by others.

Headlights help you see the road and make your vehicle more visible to other road users in fog, rain, darkness, or poor weather.

Vehicle using headlights in reduced visibility
AI-generated by Rijbewijs-online.be • WCIT • CC BY-SA
Why should you avoid keeping the clutch pedal pressed while driving?

466. Why should you avoid keeping the clutch pedal pressed while driving?

It applies the parking brake.
✓ It reduces engine braking and vehicle control.
It increases tyre pressure.
It locks the steering.

Keeping the clutch pedal pressed while the vehicle is moving disconnects the engine from the transmission. This reduces engine braking and can reduce your control of the vehicle.

Clutch held down while a vehicle is moving
AI-generated by Rijbewijs-online.be • WCIT • CC BY-SA
Why should motorcyclists take extra care on wet road markings?

467. Why should motorcyclists take extra care on wet road markings?

✓ They can provide less grip than the surrounding road.
They can make the brakes overheat.
They can prevent the indicators from working.
They can increase the motorcycle's engine temperature.

Wet painted road markings can provide less grip than the surrounding road surface. Ride smoothly over them and avoid sudden braking, acceleration or steering that could cause the tyres to lose grip.

Motorcycle approaching wet painted road markings
AI-generated by Rijbewijs-online.be • WCIT • CC BY-SA
Why is it dangerous to cross while listening to loud music?

468. Why is it dangerous to cross while listening to loud music?

Drivers may not hear you crossing.
Music can make you lose your balance.
It makes you walk more slowly across the road.
✓ You may not hear approaching traffic.

Loud music can reduce your awareness of vehicles, bicycles, horns, and other warning sounds.

Pedestrian listening to music while crossing the road
AI-generated by Rijbewijs-online.be • WCIT • CC BY-SA
What should you do if your windscreen becomes covered with mud or spray?

469. What should you do if your windscreen becomes covered with mud or spray?

Continue driving and wait for the spray to clear.
Increase speed so the airflow clears the windscreen.
✓ Slow down and use the washers and wipers to restore clear vision.
Switch off the wipers until the windscreen dries.

Clear visibility is essential. Slow down safely and use your washers and wipers until you can see the road clearly again.

Mud and spray obscuring a vehicle's windscreen
AI-generated by Rijbewijs-online.be • WCIT • CC BY-SA
Which gear is used to drive a manual vehicle backwards?

470. Which gear is used to drive a manual vehicle backwards?

Neutral.
✓ R (Reverse).
2nd gear.
1st gear.

Select R (Reverse) when you need to drive a manual vehicle backwards. The vehicle should be stationary before Reverse is selected.

Manual gear lever and gear-selection pattern
AI-generated by Rijbewijs-online.be • WCIT • CC BY-SA
What does this vehicle-control symbol indicate?

471. What does this vehicle-control symbol indicate?

Child safety lock.
Central door locking.
Seat-belt reminder.
✓ Passenger airbag deactivation.

This control allows the front passenger airbag to be deactivated on vehicles equipped with this function. The airbag must be deactivated when a rear-facing child restraint is used on the front passenger seat.

Front passenger airbag deactivation control
AI-generated by Rijbewijs-online.be • WCIT • CC BY-SA
How should tyre pressure normally be checked?

472. How should tyre pressure normally be checked?

✓ When the tyres are cold, using the manufacturer's recommended pressure.
By looking at whether the tyres appear firm.
Immediately after a long or high-speed journey.
Only by a certified maintenance service.

Tyre pressure rises as tyres become warm. Check them when cold and use the pressure specified on the vehicle label or in the owner's manual.

Checking a vehicle's tyre pressure
AI-generated by Rijbewijs-online.be • WCIT • CC BY-SA
What should you do before driving away after charging an electric vehicle?

473. What should you do before driving away after charging an electric vehicle?

Leave the cable connected until the vehicle starts moving.
✓ Disconnect the charging cable and secure it properly.
Drive forward slowly to disconnect the plug.
Place the cable loosely beside the charging bay.

Before driving away, disconnect the charging cable correctly and return it to the charger or store it securely in the vehicle, as appropriate. Close the charging port and check that the area around the vehicle is clear.

Disconnecting an electric vehicle after charging
AI-generated by Rijbewijs-online.be • WCIT • CC BY-SA
How should luggage be carried on a motorcycle?

474. How should luggage be carried on a motorcycle?

Loosely strapped so it can move with the motorcycle.
✓ Securely and evenly, without affecting balance or control.
Hanging from the handlebars if the luggage is light.
As high as possible so it stays away from the wheels.

Motorcycle luggage should be securely fastened and sensibly distributed. A loose, uneven or badly positioned load can affect balance, steering and braking, or become caught in moving parts.

Luggage carried on a motorcycle
AI-generated by Rijbewijs-online.be • WCIT • CC BY-SA
What does a green traffic light mean?

475. What does a green traffic light mean?

You may turn in any direction without checking the signs.
You have priority over all other road users.
You may enter even if traffic is blocking the junction.
✓ You may proceed if it is safe.

A green light allows you to continue, but you must still watch for pedestrians, cyclists, and other road users.

Green traffic light at a junction
AI-generated by Rijbewijs-online.be • WCIT • CC BY-SA
What should cyclists do after a collision or hard fall?

476. What should cyclists do after a collision or hard fall?

Test the bicycle by riding it before checking for damage.
Check only the parts that were directly involved in the fall.
Check only the bicycle and ignore minor injuries.
✓ Check yourself and inspect the bicycle before riding again.

A fall can damage the brakes, wheels, frame, handlebars, or helmet. Injuries may also not be immediately obvious.

Checking a bicycle after a fall or collision
AI-generated by Rijbewijs-online.be • WCIT • CC BY-SA
Why should you reduce speed when approaching roadworks?

477. Why should you reduce speed when approaching roadworks?

To reduce exhaust gases near construction sites.
✓ Road workers, narrow lanes, and unexpected hazards may be present.
To keep construction dust off the windscreen.
To reduce wear on the vehicle suspension.

Roadworks can involve workers, machinery, changing lane layouts, and uneven surfaces. Lower speed gives you more time to react.

Vehicle approaching a roadworks area
AI-generated by Rijbewijs-online.be • WCIT • CC BY-SA
What does turning a traditional ignition switch to OFF normally do?

478. What does turning a traditional ignition switch to OFF normally do?

Releases the parking brake.
Selects accessory power.
✓ Switches off the engine and ignition systems.
Operates the starter motor.

Turning a traditional ignition switch to OFF switches off the engine and ignition systems. The key can then normally be moved to the LOCK position and removed.

OFF position on a traditional ignition switch
AI-generated by Rijbewijs-online.be • WCIT • CC BY-SA
What should you do if you see loose gravel on the road?

479. What should you do if you see loose gravel on the road?

Brake firmly before the tyres begin to slide.
✓ Slow down and avoid sudden steering or braking.
Follow the vehicle ahead closely in its tyre tracks.
Maintain your speed and avoid using the brakes.

Loose gravel reduces grip and can make the vehicle skid. Slow down and use smooth steering and braking.

Vehicle on a loose gravel road
AI-generated by Rijbewijs-online.be • WCIT • CC BY-SA
What should you do if another driver does not give way when they should?

480. What should you do if another driver does not give way when they should?

Use the horn and continue at the same speed.
Move closer so the other driver is forced to give way.
Accelerate so you pass through first.
✓ Slow down and avoid a collision.

Even if you have priority, safety comes first. Slow down, stay calm, and avoid creating a dangerous situation.

Conflicting vehicle movements at a junction
AI-generated by Rijbewijs-online.be • WCIT • CC BY-SA
Why should you be especially alert for wild animals at dawn and dusk?

481. Why should you be especially alert for wild animals at dawn and dusk?

✓ Many animals are more active at these times.
Road signs are harder for animals to recognise.
Animals cannot see vehicles during daylight.
Speed limits change automatically at dawn and dusk.

Many wild animals are most active around dawn and dusk, when visibility may also be reduced.

Wild animal beside a road in low light
AI-generated by Rijbewijs-online.be • WCIT • CC BY-SA
Which signs may indicate that you are becoming too tired to drive safely?

482. Which signs may indicate that you are becoming too tired to drive safely?

Wanting to adjust the cabin temperature.
Feeling comfortable and relaxed.
✓ Yawning, heavy eyelids, and difficulty concentrating.
Feeling hungry and slightly thirsty.

Warning signs of driver fatigue can include repeated yawning, heavy eyelids, difficulty concentrating, wandering thoughts, and trouble maintaining a steady road position. These signs mean you should stop and rest before continuing.

Driver showing signs of fatigue
AI-generated by Rijbewijs-online.be • WCIT • CC BY-SA
Which vehicles are especially vulnerable to strong crosswinds?

483. Which vehicles are especially vulnerable to strong crosswinds?

Low, heavily loaded vehicles.
✓ High-sided vehicles such as trucks, buses, and vans.
Vehicles with full fuel tanks.
Electric vehicles.

High-sided vehicles can be pushed sideways because of their large side area. Cyclists and motorcyclists can also be strongly affected by sudden gusts.

High-sided vehicle exposed to crosswinds
AI-generated by Rijbewijs-online.be • WCIT • CC BY-SA
You must stop at a red traffic light.

484. You must stop at a red traffic light.

✓ True.
False.

A red traffic light means you must stop and wait until it is allowed to proceed.

Vehicle stopped at a red traffic light
AI-generated by Rijbewijs-online.be • WCIT • CC BY-SA
Where should you normally wait after a breakdown on a high-speed road?

485. Where should you normally wait after a breakdown on a high-speed road?

✓ Behind a safety barrier and well away from the vehicle and traffic.
Between the vehicle and the safety barrier.
In front of the vehicle while facing approaching traffic.
On the verge beside the broken-down vehicle.

A stationary vehicle can be struck by passing traffic. Waiting behind a barrier provides better protection.

People waiting behind a safety barrier after a breakdown
AI-generated by Rijbewijs-online.be • WCIT • CC BY-SA
What does this vehicle-control symbol indicate?

486. What does this vehicle-control symbol indicate?

Mirror folding.
✓ Exterior mirror adjustment.
Seat adjustment.
Central door locking.

This control adjusts the vehicle's exterior mirrors. The driver normally selects the left or right mirror and then moves the control to change its angle.

Control for adjusting the exterior mirrors
AI-generated by Rijbewijs-online.be • WCIT • CC BY-SA
Why should you not use water on a fire involving live electrical equipment?

487. Why should you not use water on a fire involving live electrical equipment?

Water prevents the power supply from switching off.
Water makes electrical cables harder to disconnect.
✓ Water can conduct electricity and create an electric-shock hazard.
Water can make the electrical equipment restart.

Do not use water on a fire involving energised electrical equipment, because water can conduct electricity and create a serious electric-shock hazard. Keep clear, disconnect the power only if it is safe to do so, and call the emergency services. Use only a suitable fire extinguisher if it is safe and you know how to use it.

Fire involving live electrical equipment
AI-generated by Rijbewijs-online.be • WCIT • CC BY-SA
What does this vehicle-control symbol indicate?

488. What does this vehicle-control symbol indicate?

Bonnet release.
✓ Fuel-filler flap release.
Parking brake.
Boot release.

This control releases the fuel-filler flap, allowing access to the vehicle's fuel filler.

Release control for the fuel-filler flap
AI-generated by Rijbewijs-online.be • WCIT • CC BY-SA
What should you do if a red warning light appears with an unusual noise?

489. What should you do if a red warning light appears with an unusual noise?

Ignore the noise if the warning light later goes out.
✓ Stop safely, switch off the engine, and seek assistance.
Continue slowly if the vehicle still responds normally.
Wait until the next service to have it checked.

A red warning combined with an unusual noise may indicate a serious fault. Continuing could cause damage or loss of control.

Red dashboard warning requiring the driver's attention
AI-generated by Rijbewijs-online.be • WCIT • CC BY-SA
What should you do when meeting another vehicle on a narrow mountain road?

490. What should you do when meeting another vehicle on a narrow mountain road?

Drive onto the roadside without checking the surface.
Maintain speed and pass as closely as possible.
✓ Slow down and use a safe passing place if necessary.
Stop where the road is narrowest and wait.

Narrow mountain roads may not provide enough space for two vehicles. Reduce speed and cooperate to pass safely.

Vehicles meeting on a narrow mountain road
AI-generated by Rijbewijs-online.be • WCIT • CC BY-SA
What should cyclists do near a large vehicle that may be turning?

491. What should cyclists do near a large vehicle that may be turning?

Pass quickly before the vehicle starts turning.
✓ Stay back and do not pass on the turning side.
Move alongside it if there appears to be enough space.
Ride beside it so the driver can see you.

Large vehicles need extra space to turn and may move across a cyclist's path. Remaining behind is usually safer.

Cyclist near a turning large vehicle
AI-generated by Rijbewijs-online.be • WCIT • CC BY-SA
What does this dashboard symbol indicate?

492. What does this dashboard symbol indicate?

✓ Forward-collision warning.
Adaptive cruise control.
Electronic stability control.
Lane-departure warning.

This symbol relates to the forward-collision warning or automatic emergency braking system. It may warn the driver when the vehicle detects a risk of collision with traffic ahead.

Forward-collision warning symbol on the dashboard
AI-generated by Rijbewijs-online.be • WCIT • CC BY-SA
Why are tyre condition and pressure especially important on a motorcycle?

493. Why are tyre condition and pressure especially important on a motorcycle?

✓ They directly affect grip, stability, and braking.
They affect only comfort at high speed.
They matter only when carrying a passenger.
They mainly affect the engine temperature.

A motorcycle relies on a relatively small area of tyre contact with the road. Correct tyre pressure, tread and condition are important for grip, steering, stability and braking. Check the tyres regularly and follow the manufacturer's recommended pressures.

Checking the condition of a motorcycle tyre
AI-generated by Rijbewijs-online.be • WCIT • CC BY-SA
What should you do if your motorcycle helmet visor starts to fog?

494. What should you do if your motorcycle helmet visor starts to fog?

✓ Reduce speed and clear the visor safely.
Close all helmet vents completely.
Keep riding at the same speed until it clears.
Look around the side of the visor instead.

A fogged visor can seriously reduce your view of the road. Reduce speed and use the helmet's ventilation, demisting or anti-fog features where available. If you cannot restore a clear view safely, stop in a safe place before continuing.

Misted visor on a motorcycle helmet
AI-generated by Rijbewijs-online.be • WCIT • CC BY-SA
What should you do if you approach slow-moving farm machinery?

495. What should you do if you approach slow-moving farm machinery?

Drive close behind until there is room to pass.
✓ Keep a safe distance and overtake only when safe.
Overtake as soon as the road becomes slightly wider.
Use your horn so the driver moves aside.

Farm machinery may be wide, slow, or turn unexpectedly. Keep distance and only overtake when you have a clear view and enough space.

Vehicle approaching slow-moving farm machinery
AI-generated by Rijbewijs-online.be • WCIT • CC BY-SA
What should you normally do before starting an automatic vehicle?

496. What should you normally do before starting an automatic vehicle?

Select D and press the accelerator.
✓ Select P or N and press the brake pedal.
Leave the selector between two positions.
Select R and release the parking brake.

Before starting an automatic vehicle, make sure P (Park) or N (Neutral) is selected and press the brake pedal. Many automatic vehicles will only allow the engine to start when these conditions are met.

Gear selector and brake before starting an automatic vehicle
AI-generated by Rijbewijs-online.be • WCIT • CC BY-SA
What should you do if an overtaking vehicle is coming toward you?

497. What should you do if an overtaking vehicle is coming toward you?

Move closer to the centre so the other driver notices you.
✓ Slow down and move slightly aside if safe.
Brake sharply as soon as the vehicle enters your lane.
Maintain your speed and expect the other driver to return to their lane.

If an oncoming vehicle creates danger while overtaking, reduce speed and make space if it is safe to do so. Avoid sudden movements that could create an additional hazard.

Oncoming vehicle overtaking into the driver's lane
AI-generated by Rijbewijs-online.be • WCIT • CC BY-SA
Why should you avoid overloading a trailer?

498. Why should you avoid overloading a trailer?

It makes the trailer easier to control.
It keeps the trailer more stable in strong winds.
✓ It can reduce stability and place excessive strain on the vehicle.
It improves braking on steep roads.

Overloading can affect braking, steering, tyres, suspension, and trailer stability. Always remain within permitted limits. After loading, check that the load is secure and correctly distributed before starting your journey.

Loaded trailer and towing limits
AI-generated by Rijbewijs-online.be • WCIT • CC BY-SA
Where should passengers get in or out of a vehicle when possible?

499. Where should passengers get in or out of a vehicle when possible?

On the side closest to approaching traffic.
From the rear door nearest the centre of the road.
✓ On the side away from moving traffic.
Through whichever door opens first.

Passengers should get in or out on the side away from moving traffic whenever possible. This is particularly important for children, who may not recognise approaching traffic or other road users. Before opening any door, check that it is safe.

Passenger leaving a vehicle on the side away from traffic
AI-generated by Rijbewijs-online.be • WCIT • CC BY-SA
What should you do before driving down a long, steep hill?

500. What should you do before driving down a long, steep hill?

✓ Reduce speed and select a suitable lower gear.
Coast in neutral to save fuel.
Select a higher gear to reduce engine resistance.
Accelerate before the descent to maintain momentum.

A lower gear helps control your speed and reduces the amount of continuous braking needed on a long descent.

Vehicle approaching a long, steep descent
AI-generated by Rijbewijs-online.be • WCIT • CC BY-SA