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.
Transportation systems can be made greener by promoting the use of public transportation, encouraging carpooling and ride-sharing, investing in renewable energy sources for vehicles, promoting electric vehicles, and implementing infrastructure for biking and walking. Additionally, reducing the need for long-distance commuting through telecommuting and flexible work arrangements can also help reduce carbon emissions.
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
Greener
the U.S. Department of Transportation.