题目
With petroleum reserves (石油储量) decreasing，the search is on to replace gas with a cleaner，greener alternative.Though much eco－talk has centered on biofuels from corn and soybeans，the biofuel that looks more likely to replace petroleum comes from a most unlikely source：algae (藻类)． Algae，like corn，soybeans，and other crops，grow via photosynthesis (光合作用) and can be processed into fuel oil.However，they yield 30 times more energy than land crops such as soybeans，according to the U．S.Department of Energy.Many algae species also can grow in saltwater and polluted water－while corn and soy require arable land and fresh water that will be in short supply as the world's population balloons. “If you replaced all the diesel (柴油) in the U．S.with soy biodiesel，it would take half the land mass of the U．S.to grow those soybeans，”says Matt Caspari，chief executive of Aurora Biofuels，a Berkeley，Calif.－based private firm that specializes in algae oil technology.On the other hand，the Energy Department says that if algae fuel replaced all the petroleum fuel in the United States，it would require 15,000 square miles，which is a few thousand miles larger that Maryland (12,407 square miles)，the 42nd state in land area. Another bonus：Because algae can be grown just about anywhere in a closed space，they 're being tested at several power plants across the nation as a carbon absorber.Smokestack emissions (烟囱排放物) can be pumped directly into the ponds，feeding the algae while keeping greenhouse gases out of the atmosphere. Although processing technology for algae fuel—also known as “oilgae” in some environmentalist circles—is improving，it's still years away from reaching your local gas pump.“It's just a question of cost，because no large－scale facilities have been built yet，” Caspari says. 【小题1】The underlined word “yield” in Paragraph 2 can be replaced by “________”． A．control B．require C．produce D．grow 【小题2】Compared with corn and soybeans，algae ________. A．may pollute water and soil B．can grow in poor conditions C．provide much less energy D．need more special care 【小题3】According to Paragraph 3，one of the advantages of algae fuel is that ________. A．it can be used more widely B．it is more easy to produce C．it needs much less land D．it costs much less money 【小题4】What do we learn about algae from Paragraph 4? A．Algae help protect the environment. B．People can grow algae anywhere. C．Fish can get more oxygen from algae. D．Algae produce less waste.
With petroleum reserves (石油储量) decreasing，the search is on to replace gas with a cleaner，greener alternative.Though much eco－talk has centered on biofuels from corn and soybeans，the biofuel that looks more likely to replace petroleum comes from a most unlikely source：algae (藻类)．
Algae，like corn，soybeans，and other crops，grow via photosynthesis (光合作用) and can be processed into fuel oil.However，they yield 30 times more energy than land crops such as soybeans，according to the U．S.Department of Energy.Many algae species also can grow in saltwater and polluted water－while corn and soy require arable land and fresh water that will be in short supply as the world's population balloons.
“If you replaced all the diesel (柴油) in the U．S.with soy biodiesel，it would take half the land mass of the U．S.to grow those soybeans，”says Matt Caspari，chief executive of Aurora Biofuels，a Berkeley，Calif.－based private firm that specializes in algae oil technology.On the other hand，the Energy Department says that if algae fuel replaced all the petroleum fuel in the United States，it would require 15,000 square miles，which is a few thousand miles larger that Maryland (12,407 square miles)，the 42nd state in land area.
Another bonus：Because algae can be grown just about anywhere in a closed space，they 're being tested at several power plants across the nation as a carbon absorber.Smokestack emissions (烟囱排放物) can be pumped directly into the ponds，feeding the algae while keeping greenhouse gases out of the atmosphere.
Although processing technology for algae fuel—also known as “oilgae” in some environmentalist circles—is improving，it's still years away from reaching your local gas pump.“It's just a question of cost，because no large－scale facilities have been built yet，” Caspari says.
【小题1】The underlined word “yield” in Paragraph 2 can be replaced by “________”．
【小题2】Compared with corn and soybeans，algae ________.
【小题3】According to Paragraph 3，one of the advantages of algae fuel is that ________.
【小题4】What do we learn about algae from Paragraph 4?
Algae，like corn，soybeans，and other crops，grow via photosynthesis (光合作用) and can be processed into fuel oil.However，they yield 30 times more energy than land crops such as soybeans，according to the U．S.Department of Energy.Many algae species also can grow in saltwater and polluted water－while corn and soy require arable land and fresh water that will be in short supply as the world's population balloons.
“If you replaced all the diesel (柴油) in the U．S.with soy biodiesel，it would take half the land mass of the U．S.to grow those soybeans，”says Matt Caspari，chief executive of Aurora Biofuels，a Berkeley，Calif.－based private firm that specializes in algae oil technology.On the other hand，the Energy Department says that if algae fuel replaced all the petroleum fuel in the United States，it would require 15,000 square miles，which is a few thousand miles larger that Maryland (12,407 square miles)，the 42nd state in land area.
Another bonus：Because algae can be grown just about anywhere in a closed space，they 're being tested at several power plants across the nation as a carbon absorber.Smokestack emissions (烟囱排放物) can be pumped directly into the ponds，feeding the algae while keeping greenhouse gases out of the atmosphere.
Although processing technology for algae fuel—also known as “oilgae” in some environmentalist circles—is improving，it's still years away from reaching your local gas pump.“It's just a question of cost，because no large－scale facilities have been built yet，” Caspari says.
【小题1】The underlined word “yield” in Paragraph 2 can be replaced by “________”．
| A．control | B．require |
| C．produce | D．grow |
| A．may pollute water and soil |
| B．can grow in poor conditions |
| C．provide much less energy |
| D．need more special care |
| A．it can be used more widely |
| B．it is more easy to produce |
| C．it needs much less land |
| D．it costs much less money |
| A．Algae help protect the environment. |
| B．People can grow algae anywhere. |
| C．Fish can get more oxygen from algae. |
| D．Algae produce less waste. |
题目解答
答案
【小题1】C
【小题2】B
【小题3】C
【小题4】A
【小题2】B
【小题3】C
【小题4】A
解析
步骤 1：理解“yield”的含义
“yield”在第二段中的含义是“产生”，因为上下文提到藻类产生的能量是大豆等陆地作物的30倍。
步骤 2：比较藻类与玉米和大豆
藻类可以在盐水和污染水中生长，而玉米和大豆需要可耕地和淡水，这表明藻类可以在较差的条件下生长。
步骤 3：理解藻类燃料的优势
根据第三段，藻类燃料的一个优势是它需要的土地面积比玉米和大豆少得多。
步骤 4：理解藻类对环境的影响
根据第四段，藻类可以作为碳吸收剂，帮助减少温室气体排放，从而保护环境。
“yield”在第二段中的含义是“产生”，因为上下文提到藻类产生的能量是大豆等陆地作物的30倍。
步骤 2：比较藻类与玉米和大豆
藻类可以在盐水和污染水中生长，而玉米和大豆需要可耕地和淡水，这表明藻类可以在较差的条件下生长。
步骤 3：理解藻类燃料的优势
根据第三段，藻类燃料的一个优势是它需要的土地面积比玉米和大豆少得多。
步骤 4：理解藻类对环境的影响
根据第四段，藻类可以作为碳吸收剂，帮助减少温室气体排放，从而保护环境。