hce_tcu
112年
英文
第 39 題
📖 題組：
【B】 Most of Africa is a series of stable, ancient plateau surfaces, low in the north and west and higher in the south and east. The plateau is composed mainly of metamorphic rock that has been overlaid in places by sedimentary rock. The escarpment of the plateau is often in close proximity to the coast, thus leaving the continent with a generally narrow coastal plain; in addition, the escarpment forms barriers of falls and rapids in the lower courses of rivers that impede their use as transportation routes into the interior. The entire African continent is surrounded by a narrow continental shelf. The lowest point on the continent is 155 meters below sea level in Lake Assal in Djibouti; the highest point is Mt. Uhuru, a peak of Kilimanjaro in Tanzania, at 5,895 meters in elevation. The continent’s largest river is the Nile, which is also the world’s longest river. The largest lake is Victoria, which is the world’s second largest freshwater lake. There are a number of other rivers and lakes throughout the continent. These lakes and major rivers form an important inland transportation system. Geologists have long noted the excellent fit between the coast of Africa at the Gulf of Guinea and the Brazilian coast of South America, and they have evidence that Africa formed the center of a large ancestral supercontinent known as Pangaea. Pangaea began to break apart in the Jurassic period to form Gondwanaland, which included Africa, the other southern continents, and India. South America was separated from Africa 76 million years ago, when the floor of the South Atlantic Ocean was opened up by seafloor spreading. There is also evidence of one-time connections between Northwest Africa and Eastern North America, North Africa and Europe, Madagascar and India, and Southeast Africa and Antarctica. 76 million years is, of course, a blink of an eye in geological time. The long-term future of Africa as a continent is therefore bleak; although we are accustomed to thinking of Africa as an ancient land and as the birthplace of humanity, it is just as susceptible to the geological forces of a cooling planet as the other continents. Having been formed by these forces, it is unlikely that a continent resembling Africa will still exist in 100 million years.
【B】 Most of Africa is a series of stable, ancient plateau surfaces, low in the north and west and higher in the south and east. The plateau is composed mainly of metamorphic rock that has been overlaid in places by sedimentary rock. The escarpment of the plateau is often in close proximity to the coast, thus leaving the continent with a generally narrow coastal plain; in addition, the escarpment forms barriers of falls and rapids in the lower courses of rivers that impede their use as transportation routes into the interior. The entire African continent is surrounded by a narrow continental shelf. The lowest point on the continent is 155 meters below sea level in Lake Assal in Djibouti; the highest point is Mt. Uhuru, a peak of Kilimanjaro in Tanzania, at 5,895 meters in elevation. The continent’s largest river is the Nile, which is also the world’s longest river. The largest lake is Victoria, which is the world’s second largest freshwater lake. There are a number of other rivers and lakes throughout the continent. These lakes and major rivers form an important inland transportation system. Geologists have long noted the excellent fit between the coast of Africa at the Gulf of Guinea and the Brazilian coast of South America, and they have evidence that Africa formed the center of a large ancestral supercontinent known as Pangaea. Pangaea began to break apart in the Jurassic period to form Gondwanaland, which included Africa, the other southern continents, and India. South America was separated from Africa 76 million years ago, when the floor of the South Atlantic Ocean was opened up by seafloor spreading. There is also evidence of one-time connections between Northwest Africa and Eastern North America, North Africa and Europe, Madagascar and India, and Southeast Africa and Antarctica. 76 million years is, of course, a blink of an eye in geological time. The long-term future of Africa as a continent is therefore bleak; although we are accustomed to thinking of Africa as an ancient land and as the birthplace of humanity, it is just as susceptible to the geological forces of a cooling planet as the other continents. Having been formed by these forces, it is unlikely that a continent resembling Africa will still exist in 100 million years.
The author thinks that the history of Africa is _____.
- A As old as the earth itself
- B Extremely long
- C Quite long
- D Extremely short
思路引導 VIP
請留意文章最後一段的第一句話。作者將「7,600 萬年」這個時間跨度放在「地質時間（geological time）」的背景下進行比較時，他使用了一個關於「身體感官動作」的譬喻。請思考那個譬喻所代表的時間感是長還是短？
🤖
AI 詳解
AI 專屬家教
地質時間的相對性
太棒了！你能精準捕捉到作者在文末轉折處的弦外之音，這代表你的閱讀細緻度非常高。這道題目的正確答案之所以是 (D) Extremely short，關鍵在於最後一段的開頭：作者提到 7,600 萬年在地質時間（geological time）的尺度下，不過是「眨眼之間」（a blink of an eye）。雖然我們習慣將非洲視為人類文明的搖籃、一塊古老的土地，但作者從地殼變動的宏觀視角出發，認為大陸的生命週期在行星演化中其實非常短暫，甚至預言 1 億年後非洲可能就不再以現在的面貌存在。
難度評析：跳脫直覺陷阱
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