2. When are windows the weak link in a building？

　　A In the cold winter.

　　B In the hot summer.

　　C When air conditioners are turned on.

　　D Both A and B.

　　3. What are smart windows，according to Paragraph 4？

　　A Windows that are coated.

　　B Windows that are glazed.

　　C Windows the color of which can be changed.

　　D Windows that have many layers.

　　4. To make electrochromic windows change color，what is applied to the window glass？

　　A Electricity.

　　B Tungsten oxide.

　　C A battery.

　　D A voltage.

　　5. What will he the benefit if the research on smart windows turns out to be successful，according to the last paragraph？

　　A The buildings will look different.

　　B Windows can be as large as you want.

　　C We may not need air conditioners any more.

　　D They are less expensive than traditional windows.

　　答案與題解：

　　1. A 第一段告訴我們窗戶因為讓陽光進入房間，并且為房間提供熱源，所以節(jié)約了能源。第二段說，窗戶使人們能接觸外部世界。所以B、C和D都說明了窗戶的重要性。第一段最后一句說，研究者正在實驗能讓窗戶變換亮度，但并沒有說已經(jīng)實驗成功，所以A是錯誤的說法，是正確選擇。

　　2. D 短文第三段的第一句說：windows are the weak link in a building，接下來是對這句話分寒冬和炎夏做了說明。所以D是正確選擇。

　　3. C 第四段告訴我們，多年來，科學家已研究出多種通過窗戶節(jié)能的辦法，而smart windows 使用的技術使窗戶能變換顏色。所以C是正確選擇。

　　4. B 第五段第二句提供了答案。a sheet of glass coated with thin layers of chemical compound such as tungsten oxide中的coated是“涂上一層薄薄的……”的意思。

　　5. C 短文最后一段的第五句提供了答案。