As is known for all that global warming is one of the greatest challenges to the human race,one may ask can an ordinary person do anything to help?The answer is yes,you can.Every one can does something to help by leading a greener life.We can start from saving energy by choosing the energy saving bulb,using public tranportation.Only use airconditioner when it is most needed and never leave it on when you are not using it.You can become a greener person as long as you pick this green habit.