Unit 4  Global warming

keys: 1)i will go abroad on condition that i earn enough money.  2) we will help you on condition that/as long as you can offer us the proper reason.vi 重點句子 （旨在提供句子結(jié)構(gòu)等所需材料）some byproducts of this process are called “greenhouse” gases, the most important one of which is carbon dioxide. 這個升溫過程的一些副產(chǎn)品就叫 “溫室”氣體,其中最重要的就是二氧化碳.[解釋]one/all/every/each/part… of which(whom)引導(dǎo)的定語從句，表示“他（它）們中的一個/所有/每/部分……”[典例] 1) i have three good friends, all of whom have emigrated to u.s.a.我有三個好朋友，他們都移民美國了。 2) here are many kitties, two of which are yellow.這有許多小貓，其中兩只是黃色的。 [練習(xí)] 漢譯英我有三個叔叔,其中最年輕的叔叔三年前去了澳洲.       _______________________________________________________________________________________key: i have three uncles, the youngest one of whom went to australia three years ago.二、課文要點1課文詞匯等填空（旨在復(fù)習(xí)本課文中的單詞拼寫和主要詞語等）根據(jù)課文內(nèi)容完成下面語法填空，注意單詞拼寫和詞語用法： when   1    (compare) with most natural changes, that the temperature of the earth rose about one degree fahrenheit during the 20th century is quite shocking. and it’s human activity    2    has caused this   3    (全球的) warming rather   4    a random but natural   5    （現(xiàn)象）. dr janice foster explains that we add huge     6      of extra carbon dioxide to the atmosphere by burning fossil fuels. from the second     7    （圖表）and the discovery of charles keeling, all scientists believe that the burning of more and more fossil fuels    has resulted   8   the increase in carbon dioxide. greenhouse gases continue to build up. some think that the trend would be a     9     (災(zāi)難). on the other hand, george hambley      10      (聲明) that more carbon dioxide would encourage a greater range of animals and bring us a better life. 答案：1.compared      2.that        3.global       4.rather            5.phenomenon     6.quantities      7.graph       8.in         9.catastrophe       10.states