D

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.

    "Life is speeding up. Everyone is getting unwell." This may sound like something someone would say today. But in fact, an unknown person who lived in Rome in AD 53 wrote it. 

We all love new inventions. They are exciting, amazing and can even change our lives. But have all these developments really improved the quality of our lives?

    Picture this, you're rushing to finish your homework on the computer. Your mobile phone rings, a QQ message from your friend appears on the screen, the noise from the television is getting louder and louder. Suddenly the computer goes blank and you lose all your work. Now you have to stay up all night to get it done. How happy do you feel?

Inventions have speeded up our lives so much that they often leave up feeling stressed and tired. Why do you think people who live far away from noisy cities, who have no telephones, no car, not even any electricity often seem to be happier? Perhaps because they live a simpler live.

     One family in the UK went "back in time" to see what life was like without all the inventions we have today. The grandparents, with their daughter, and grandsons Benjamin, 10 and Thomas, 7, spent nine weeks in a 1940s house. They had no washing machine, microwave, computer or mobile phones. The grandmother, Lyn, said, "The more things you have, the more difficult life becomes." The boys said they fought less. Probably, they said, because there was less to fight over, such as their computer. Benjamin also noticed that his grandmother had changed from being a "trendy, beer-drinking granny, to one who cooked things"   

—I think if you keep memorizing several words one day, you will __________.

—I don't think so. We should discuss it one more time.