高中英语北师大版版选修8课件：Unit+22+Section+Ⅰ+Warm-up+&+Lesson+1+—+Pre-reading

The greenhouse effect is important. Without the greenhouse effect， the Earth would not be warm enough for humans to live. But if the greenhouse effect becomes stronger， it could make the Earth warmer than usual. Even a little extra warming may cause problems for humans， plants， and animals.
The Earth's atmosphere is all around us. It is the air that we breathe. Greenhouse gases in the atmosphere behave much like the glass panes 窗玻璃 in a greenhouse. Sunlight enters the Earth's atmosphere， passing through the blanket of greenhouse gases. As it reaches the Earth's surface， land， water， and biosphere 生 物圈 absorb the sunlight's energy. Once absorbed， this energy is sent back into the atmosphere. Some of the energy passes back into space， but much of it remains trapped in the atmosphere by the greenhouse gases， causing our world to heat up.
The greenhouse effect is the rise in temperature that the Earth experiences because certain gases in the atmosphere 大 气； 大气层 trap energy from the sun. Without these gases，heat would escape back into space and Earth's average temperature would be about 60° F colder. Because of how they warm our world， these gases are referred to as greenhouse gases. Have you ever seen a greenhouse？ Most greenhouses look like a small glass house. Greenhouses are used to grow plants， especially in the winter. Greenhouses work by trapping heat from the sun. The glass panels 面，板 of the greenhouse let in light but keep heat from escaping. This causes the greenhouse to heat up， much like the inside of a car parked in sunlight， and keeps the plants warm enough to live in the winter.
into注入 ⑧look
Looking ⑦speed up 加快速度
ahead 展望未来
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global warming could be one of ⑨现在分词短语facing the 21st century作后置定语，修饰 the biggest environmental the biggest environmental problems facing the 21st problems。 century⑨. But what exactly is ⑩be seen as 被看作 ⑪danger n．[C]“危险的人， global warming, why is it seen 危险的事物”。在文中为抽 10 a danger⑪， and how is it 象名词具体化。 as○ relevant⑫ to our lives?
过去分词短语作定语，修饰 something。 ④beyond one's control 超 出……的控制，不受……的控 制
④ seen as beyond our control . They ③seen as beyond our control是
claim⑤ that in the last 50 years, gases pumped into
⑥
the Earth's
atmosphere by the factories and
vehicles have been speeding up⑦ the ⑤claim/kleIm/vt.声称 ⑥pump process of global warming and affecting our climate. ahead⑧， scientists believe that
Section Ⅰ
Warm­up
& Lesson 1 — Pre­reading
[原文呈现] Can we take the heat?
In the last few decades①， scientists have reached
①Байду номын сангаасn
[读文清障] the last/past
few
decades/years/months/days 此类 短语，通常与现在完成时连用。 in 也可换成 over 或 during。 本 段和第三段均含有此类结构。
consensus② and reported that human beings are causing
changes in the Earth's climate ②consensus/kən'sensəs/n. 一 致 的 — something previously
意见
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③
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