Writing prompt: The Advantages and Disadvantages of Private Cars

Student essay:
Private cars have some advantages.First,it makes travel easier.We can go to some close places in weekends.And with the development of technology, cars is becoming more and more comfortable to ride.It's very convenient for us.
But on the other side,cars also have some disadvantages.The most important one is air pollution.There are masses of hazardous substance in the automobile exhaust.Such as carbon monoxide,sulfur dioxide,solid particles and so on.They are not only bad for the environment ,but also for our health.
In my opinion,the advantages can't be replaced.And we should develop the energy technology fast.To keep the sky blue is our common aspiration.

Corrected essay:
Private cars have some advantages. First, they make travel easier. We can go to some nearby places on weekends. And with the development of technology, cars are becoming more and more comfortable to ride. It's very convenient for us.
But on the other side, cars also have some disadvantages. The most important one is air pollution. There are masses of hazardous substances in the automobile exhaust, such as carbon monoxide, sulfur dioxide, solid particles and so on. They are not only bad for the environment, but also for our health.
In my opinion, the advantages can't be replaced. And we should develop the energy technology fast. To keep the sky blue is our common aspiration.