Text Correction TOEFL (question 1)

Hello! Could you guys read my text? And give me some opinions and suggestions? I wrote this text for the integrated writing (TOEFL). I just want to know if the text makes sense and if the grammar is right etc. Here it is:

The article explains that forest fires can have natural or human causes and that in order to burn, a forest fire requires: heat, oxygen and fuel. And in the lecture the professor explains how these fires are managed and the approach fire fighters use to fight forest fires.

The first type of a forest fires is the ground fire. It burns at or below the ground and where there is low-lying vegetation. This type of fire can burn slowly over a long period of time. The professor explains that ground fire, is most often controlled with trenches. He explains that fire fighters dig these trenches down to the layer of soil that's made up of minerals therefore it doesn’t burn.

Second, is the surface fire. This fire burns from the level ground ten feet high and it's fueled by timber litter and grasses. The professor says, that this type of fire moves quickly therefore is more difficult to contain. And also, the professor explainsthe fire fighters extinguish the flame with water and fire backs.

Third, is the crown fire. It burns the crowns of the threes. The crown fire is also the most dangerous and destructive of the forest fires, because it tends to spread very rapidly. The professor explains that the crown fire is the fastest spreading and the most difficult fire to be controlled. According to the professor, this kind of fire has to be approached from the air, where water and fire retardant chemicals are sprayed on the fire from helicopters or low-flying airplanes.


In conclusion, we have learned from the article the three different types of forest fires; the ground fire, the surface fire and the crown fire. And from the lecture we have learned how these type of fires are controlled and managed.