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You may watch a program about how the elephants in Africa destroy their habitat(居住地). Humans are much smaller than the strong elephants, but we also destroy the environment and damage the Earth in more ways than other creatures. What are some of the man-made problems that the Earth faces today?

     The TV has shown the problem of global warming (全球变暖) many times. At one time during the Ice Age, the Earth was much colder than it is now and natural forces caused the planet to warm up to the temperatures we experience now. That is the normal climate change. Global warming is an increase in the temperature of the Earth's atmosphere. It is caused by the increase in greenhouse gases.

    With higher temperatures the polar ice caps are starting to melt and add some other water to the oceans. This raises the sea level and will eventually flood low areas.

  And humans are destroying the natural habitat of all the other creatures on Earth. For example, people in South America are destroying the rainforest. Hundreds of animals and plants are on the endangered list, and they could disappear from the Earth forever.

  We waste our water and only think that the tap (水龙头) will never run out. The poor Earth is destroyed by careless human activities. The awful picture of the poor Earth can change if enough people work to save and improve the environment.

The population has {#blank#}1{#/blank#} {#blank#}2{#/blank#}1.8 million.

    We should not use more water than we actually need. If we do, we will not have enough water in the future.{#blank#}1{#/blank#}It is not a difficult question to answer. If we remove more fresh water than nature replaces, we have taken too much.

    Many cities run campaigns (运动) to get people to stop wasting water. They show them ways they can cut back on water use.{#blank#}2{#/blank#}What's more, they carry out programs that offer money to reduce water use. For example, they give people shower heads and toilets that use less water.{#blank#}3{#/blank#}

    Another threat (威胁) to our water supply is pollution. When our sources of fresh water get polluted, we can no longer use this water. This also endangers (危及) the animals that depend on the water.

    {#blank#}4{#/blank#}We can save lots of water by not letting taps (水龙头) run while we brush our teeth or by turning off taps right after washing hands. By collecting cold water when we're taking warm showers, we can also save water.{#blank#}5{#/blank#}In this way, we can make full use of water.

Because of the{#blank#}1{#/blank#} {#blank#}2{#/blank#}, the Earth's temperature is increasing.