To **pollute as little as possible** while driving, it is important to **maintain a steady speed** and avoid unnecessary acceleration and braking. This is because sudden changes in speed increase fuel consumption and, therefore, the emission of toxic gases into the atmosphere.

- **Acceleration and braking**: When you accelerate abruptly, the engine consumes more fuel than necessary, which increases pollution. Similarly, braking sharply can also lead to inefficient fuel use.

- **Efficient driving**: Maintaining a constant speed helps the engine operate more efficiently, reducing fuel consumption and pollutant emissions.

- **Pollution and toxic gases**: Vehicles emit gases that pollute the air, and efficient driving can help minimize this negative impact on the environment.

Therefore, to reduce pollution, it is advisable to drive smoothly and steadily, avoiding sudden changes in speed.