Check it, please

[lavinia94]

Do you think we rely too much on cars? What are the advantages and disadvantages of this?

I think we do, but it's because we're used to it. People usually use their cars to go to work and sometimes to travel longer distances. But nowadays people are using their cars to go to places they can go to by foot. So they contaminate the environment and become very sedentary. In our country fuel is very expensive and the short journeys can cost us a lot.
People in Italy, for example, cycle to work or other places improving their heath and saving a lot of money. It's comfortable because you don't have to worry where to park your car in the city.
By taking the metro, the bus or another public mean of transport you avoid traffic jams. Also a lot of people die every year because of car accidents.
I think we should try not to use that much the car and use more other mean of transport when it's possible.

[kazewolf]

I am neither a teacher nor am i good at english but i can provide some information.
You shouldn't start a sentence with a conjunction(eg: but,so, etc...)

In our country fuel is very expensive and the short journeys can cost us a lot.

You should include a comma after "In our country" and leave out the "the" because you are talking about a wide range of short journeys, not a definite journey.

So they contaminate the environment and become very sedentary.

"Sedentary" shouldn't be included in that same sentence because the points just do not link, the environment doesn't have anything to do with sedentary?

Other experts please correct me if I am wrong.

[billmcd]

Do you think we rely too much on cars? What are the advantages and disadvantages of this?

I think we do, but it's because we're used to it. People usually use their cars to go to work and sometimes to travel longer distances. But nowadays people are using their cars to go [STRIKE]to[/STRIKE](not necessary) places they can go to by foot. So they contaminate the environment and become very sedentary. In our country fuel is very expensive and the short journeys can cost us a lot.
People in Italy, for example, cycle to work or other places improving their health and saving a lot of money. It's comfortable because you don't have to worry where to park your car in the city.
By taking the metro, the bus or another public means of transport you avoid traffic jams. Also, a lot of people die every year because of car accidents.
I think we should try not to use that much the car a car that much and use rely more other means of transport when it's possible.

Nice work. A few suggestions/corrections.