In your opinion what are the two most important environmental problems?State your two options,give reasons and suggest solutions.

Today,the world faces many environmental problems.I am inclined to believe that Global Warming and the Greenhouse Effect are the most significant ones.However,they can be managed by finding the appropriate solutions.
It is obvious by its name that Global Warming has various effects.For example,the temperature of the planet increases more and more lately.Health problems and especially cardiovascular problems are caused by increased temperature.Not only is the planet affected,but also the humans.Furthermore,the weather is influenced by Global Warming.A rise of the sea level has been observed the last few years.Animals and plants are no exception;animals are obligated to change the place where they live and plants are experiencing difficulties in growing.People should take measures in order to reduce Global Warming.In particular,people should reduce the use of appliances which emit CFCs (Chlorofluorocarbons) and other polluting gases.Recycling should be encouraged,while deforestation should be stopped.Besides,the use of renewableand sustainable sources of energy such as solar and wing power are vital.
In addition to this,the Greenhouse Effect induces a lot of problems.Most of its effects are the same as the ones caused by Global Warming,these two environmental problems are linked closely.Greenhouse Effect makes the sea level rise and causes climate changes.As the heat is trapped in the atmosphere,a huge amount of water evaporates causing drought in many places.Apart from that,it increases the frequency of forest fires,storms,hurricanes and tropical deseases.If we want to avoid all these harmful results we should reduse greenhouse gases,use energy efficient appliances and reduce the use of vehicles.This is clearly illustrated by the attempt to diminish the number of oil-based automobiles.What is more,industries should control the waste disposal and put filters on the chimneys of the factories.
To conclude,we live in a planet which suffers from highly important problems.We must change our mentality and our devastating way of living in order to act immediately before it is too late and the situation becomes irreversible.All of us want to live in a better place,don't we?

Great work Thanasi! The only problem is, as I have already told you, that global warming is the threat to our planet and the greenhouse effect is the cause of it, not exactly a distinct threat. It is obvious that in both paragraphs of the main body you write almost the same things, so why don't you choose another problem to elaborate on, say air pollution? Think about it! :-)