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QuizTraffic rulesBangladesh

This interesting quiz helps you test your knowledge in a clear and visual way. With easy multiple-choice questions, you can quickly build confidence and learn new facts while keeping it simple, interactive, and fun.

Traffic signs
Traffic rules
Bangladesh
True/false 17 Bangladesh 14 Car controls 109 Dashboard lights 40 Priority rules 9 Pedestrians 19 Cyclists 20 Show all 581
Why should you avoid overloading a trailer?

451. 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
What should you do before driving down a long, steep hill?

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

Coast in neutral to save fuel.
Rely mainly on continuous braking to control speed.
Accelerate before the descent to maintain momentum.
✓ Reduce speed and select a suitable lower gear.

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
Why should you reduce speed when approaching roadworks?

453. Why should you reduce speed when approaching roadworks?

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

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

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

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

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

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

Use the wipers at a higher speed.
Ignore it unless the wipers stop moving.
✓ Clean the windscreen and blades, and replace worn blades.
Replace the washer pump instead of the 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
What should you expect if the engine suddenly stalls while the vehicle is moving?

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

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

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
What should you normally do before starting an automatic vehicle?

457. 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.
Select R and release the parking brake.
Leave the selector between two positions.

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 does this vehicle-control symbol indicate?

458. What does this vehicle-control symbol indicate?

Seat-belt reminder.
Child safety lock.
✓ Passenger airbag deactivation.
Airbag-system fault.

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
What does this dashboard symbol indicate?

459. What does this dashboard symbol indicate?

Low tyre pressure.
✓ Brake-pad wear warning.
Parking brake applied.
Brake-system fault.

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 check after fitting a wheel?

460. What should you check after fitting a wheel?

✓ That the wheel nuts are tightened correctly.
That the tyre is touching the wheel arch.
That the wheel can move slightly on the hub.
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
Why should you be careful when turning across oncoming traffic?

461. 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
How should luggage be carried on a motorcycle?

462. How should luggage be carried on a motorcycle?

Loosely strapped so it can move with the motorcycle.
Mostly on one side to leave the other side free.
Hanging from the handlebars if the luggage is light.
✓ Securely and evenly, without affecting balance or control.

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

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

✓ Disconnect the charging cable and secure it properly.
Place the cable loosely beside the charging bay.
Leave the cable connected until the vehicle starts moving.
Leave the charging flap open so it can cool.

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

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

Immediately behind the vehicle so you remain visible.
Between the vehicle and the safety barrier.
In front of the vehicle while facing approaching traffic.
✓ Behind a safety barrier and well away from the vehicle and traffic.

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
Which gear is used to drive a manual vehicle backwards?

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

Neutral.
1st gear.
✓ R (Reverse).
2nd 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
You may drive through an amber light without slowing down.

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

✓ False.
True.

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

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

Move toward the centre so the other driver gives way.
Stop where the road is narrowest and wait.
Drive onto the roadside without checking the surface.
✓ Slow down and use a safe passing place if necessary.

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

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

They determine how brightly the lights work.
They affect only comfort at high speed.
✓ They directly affect grip, stability, and braking.
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
Which vehicles are especially vulnerable to strong crosswinds?

469. Which vehicles are especially vulnerable to strong crosswinds?

Vehicles without winter tyres.
✓ High-sided vehicles such as trucks, buses, and vans.
Low, heavily loaded vehicles.
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
How should luggage or other cargo be carried in or on a vehicle?

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

Loosely in the boot so it can move a little.
Loosely in the passenger area for short journeys.
✓ Securely, within load limits, without blocking visibility or lights.
Where it is easiest to reach while driving.

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
What does this vehicle-control symbol indicate?

471. What does this vehicle-control symbol indicate?

Mirror folding.
Seat adjustment.
✓ Exterior mirror adjustment.
Electric window control.

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
What does this dashboard symbol indicate?

472. What does this dashboard symbol indicate?

Parking assistance.
Electronic stability control.
Lane-departure warning.
✓ Forward-collision 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
What should you do if an overtaking vehicle is coming toward you?

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

Move closer to the centre so the other driver notices you.
Accelerate to pass the danger point more quickly.
Brake sharply as soon as the vehicle enters your lane.
✓ Slow down and move slightly aside if safe.

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 not use water on a fire involving live electrical equipment?

474. 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 cause the battery to charge more quickly.
✓ Water can conduct electricity and create an electric-shock hazard.

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 a green traffic light mean?

475. What does a green traffic light mean?

You must proceed as soon as the light turns green.
✓ You may proceed if it is safe.
You may turn in any direction without checking the signs.
You may enter even if traffic is blocking the junction.

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 you do if you approach slow-moving farm machinery?

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

Overtake as soon as the road becomes slightly wider.
✓ Keep a safe distance and overtake only when safe.
Overtake even if the vehicle is signalling to turn.
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
How should you use the brake pedal during emergency braking in a vehicle with ABS?

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

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

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

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

Speed limits change automatically at dawn and dusk.
Road signs are harder for animals to recognise.
Wild animals avoid roads during the rest of the day.
✓ Many animals are more active at these times.

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
What should cyclists do after a collision or hard fall?

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

Test the bicycle by riding it before checking for damage.
✓ Check yourself and inspect the bicycle before riding again.
Continue if you feel fine and the bicycle looks normal.
Check only the parts that were directly involved in the fall.

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

480. 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?

481. Why should you use headlights in poor visibility?

✓ To see better and be seen by others.
To keep the windscreen clear.
To reduce fuel consumption.
To prevent the tyres from slipping.

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 is it dangerous to cross while listening to loud music?

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

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

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

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

To prevent your headlights from overheating.
To make it easier for other vehicles to overtake.
Because vehicles ahead cannot see you in their mirrors.
✓ You need enough space to react if traffic slows or stops.

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

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

Through whichever door opens first.
From the driver's side in every situation.
✓ On the side away from moving traffic.
On the side closest to approaching traffic.

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
You must stop at a red traffic light.

485. You must stop at a red traffic light.

False.
✓ True.

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

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

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

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 if another driver does not give way when they should?

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

✓ Slow down and avoid a collision.
Use the horn and continue at the same speed.
Move closer so the other driver is forced to give way.
Maintain your speed because you have priority.

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
What does this dashboard symbol indicate?

488. What does this dashboard symbol indicate?

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

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 should a motorcyclist do in strong crosswinds?

489. What should a motorcyclist do in strong crosswinds?

Ride as close to the edge of the road as possible.
✓ Reduce speed and be prepared for sudden gusts.
Accelerate to get through the windy area quickly.
Follow a large vehicle closely for protection from the wind.

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

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

✓ Slow down and use the washers and wipers to restore clear vision.
Use the demister instead of the washers.
Continue driving and wait for the spray to clear.
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
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?

✓ Stay back and do not pass on the turning side.
Assume the driver will wait for you before turning.
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 should you do if you see loose gravel on the road?

492. 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 does this vehicle-control symbol indicate?

493. What does this vehicle-control symbol indicate?

Front windscreen demister.
Air recirculation.
✓ Air conditioning.
Fan speed.

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
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?

Close all helmet vents completely.
Wipe the inside of the visor while riding.
Look around the side of the visor instead.
✓ Reduce speed and clear the visor safely.

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

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

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

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

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

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

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
How should tyre pressure normally be checked?

497. How should tyre pressure normally be checked?

By looking at whether the tyres appear firm.
Using the maximum pressure shown on the tyre.
Only by a certified maintenance service.
✓ When the tyres are cold, using the manufacturer's recommended pressure.

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 does this vehicle-control symbol indicate?

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

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

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

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
Why should motorcyclists take extra care on wet road markings?

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

They can increase the motorcycle's engine temperature.
They can cause the tyre pressure to rise suddenly.
✓ They can provide less grip than the surrounding road.
They can make the brakes overheat.

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