One possible version：
In order to deal with the climate change, the United Nations held the 15th Climate Change Conference in Copenhagen from Dec. 7 to Dec. 18, 2009.
We are faced with serious problems now. A large amount of greenhouse gas is emitted, resulting in global warming. What’s worse, the sea level has risen.
For that, the leaders of all countries gathered to talk about what responsibility their countries should take on. Thankfully, developed countries promised to cut emission, and offer economic help to developing countries. Meanwhile, developing countries are willing to join in slowing down the global warming as well, among which China advocates developing green economy.
On my part, it’s high time that we took measures against global warming. For one thing, we should have the factories causing serious pollution closed down. For another, cars should be used less, instead, we may ride bikes or just walk every day. Only in this way can we really cut the greenhouse emission, slow down the global warming, and eventually protect our homes.
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