I don't know, that's pretty vague. But one way would be to drive less and use a car with good gas mileage, or even a completely electric vehicle like the new Nissan Leaf.
Railroad
I'll have an answer when i have finished my coursework
The Highway Transportation System
Recycle.
The endoplasmic reticulum or ER
By eliminating the use of plastic carrier bags.
you could paint it green or put grass on it
Good transportation system
A transportation hub is a moving system
the U.S. Department of Transportation.
This system is the transportation of the blood.
Greener