Global warming is when the Earth gets hotter because of pollution. People cause it by burning things like coal and cutting down forests. Renewable energy, like sunlight and wind, is better because it doesn't hurt the Earth. In the future, we want cities to use clean energy, like the sun and wind. In a good city, we would use electric cars and buses, not gas ones, and make less trash. We should recycle and throw away trash in the right bins. Everyone can help by saving energy, recycling, and supporting green ideas to make our city better and safer.