答案與解析：
1． 分析文章標(biāo)題：The Northern Lights(北極光)
2．直接解題： 1. The Sun’s gravity（引力） is too (太...而不能...)weak(弱的， 虛弱的) to keep its plasma（等離子體） from （阻止/防止...）flowing（流動） to the Earth.
A. right B. wrong C. not mentioned
1．B． 細(xì)節(jié)題。 利用問題句中的特征詞（the Sun’s gravity, the Earth ）及細(xì)節(jié)信息詞(plasma) 共同作為答案線索， 在文章中查找答案相關(guān)句：
（第一段）The sun is stormy（狂暴的，多暴風(fēng)的） and has it own（自己的） kind of weather（氣候，天氣）. It is so（如此...以至于...） hot（熱的，辣的） and active（活躍的） that even(甚至) the Sun’s gravity （引力）cannot hold （控制）its atmosphere（大體層， 氣氛） in check! Energy（能量） flows away from （從...流出）the Sun toward（向） the Earth in a stream of （以一連串的形式）electrified（帶電的） particles（粒子） that move at speeds （以...的速度）around a million miles per（每） hour（小時）. These particles（粒子） are called（被稱為） plasma, and the stream（流，溪， 一連串） of plasma coming from（來自） the Sun is called the solar wind（太陽風(fēng)）. The more active the Sun, the stronger the solar wind.
第一個答案相關(guān)句說“太陽石如此的熱， 如此的活躍， 以至于太陽的引力無法控制住其大氣層”。根據(jù)第2個答案相關(guān)句可知“等離子體就是來自太陽大氣層”， 由此可見造成太陽不能阻止其大氣層中的等離子體流向地球的主要原因不是太陽引力的問題，而是由于太陽過于活躍， 太熱了。
2. The Earth is quite（相當(dāng)，十分） safe（安全的） with（帶有） a magnetic field （磁場）surrounding（圍繞) it to protect（保護...以防止/避免...） it from the attack(襲擊/攻擊) by the solar wind（太陽風(fēng)）.
A. right B. wrong C. not mentioned 2．A． 細(xì)節(jié)題。問題句說“四周帶有磁場的地球是十分安全的，這個磁場能防止地球受到太陽風(fēng)的攻擊”。 利用問題句中的特征詞（Earth ）及細(xì)節(jié)信息詞(magnetic field, solar wind) 共同作為答案線索， 在文章中查找答案相關(guān)句：
（第一段）The sun is stormy and has it own kind of weather. （第一題答案相關(guān)句）It is so hot and active that even the Sun’s gravity cannot hold its atmosphere in check! Energy flows away from the Sun toward the Earth in a stream of electrified particles that move at speeds around a million miles per hour. These particles are called plasma, and the stream of plasma coming from the Sun is called the solar wind. The more active the Sun, the stronger the solar wind.
The solar wind constantly （不斷地）streams（流） toward the Earth, but don’t worry（擔(dān)心） because（因為） a protective（保護的） magnetic fields surrounds（圍繞） our planet. The same magnetic field that makes your compass point north also steers the particles from the Sun to the north and south poles. The charged particles become trapped in magnetic belts around the Earth. When a large blast of solar wind crashes into the Earth’s magnetic field first gets squeezed and then the magnetic field lines break and reconnect.
(以下為第二十四講內(nèi)容) 3. Some scientists（科學(xué)家） are worrying about （正在擔(dān)心 ）the possible （可能的）disappearance（消失） of the Earth’s protective（保護的） magnetic field （磁場）in the future（將來）.
A. right B. wrong C. not mentioned
3．C． 細(xì)節(jié)題。利用問題句中的特征詞（ the Earth ）及細(xì)節(jié)信息詞(scientists, magnetic field) 共同作為答案線索， 在文章中查找答案相關(guān)句：順著上一題的答案位置往下查找答案相關(guān)句：scientists這個線索詞連同其近義詞或詞義相關(guān)詞，這樣的信息也沒有在文章中出現(xiàn)，因此判斷該問題句的內(nèi)容在文章中沒有被提到。
(第2題的答案相關(guān)句) The solar wind constantly streams toward the Earth, but don’t worry because a protective magnetic fields surrounds our planet. The same magnetic field that makes your compass point north also steers the particles from the Sun to the north and south poles. The charged particles become trapped in magnetic belts around the Earth. When a large blast of solar wind crashes into the Earth’s magnetic field first gets squeezed and then the magnetic field lines break and reconnect.
The breaking and reconnecting of the magnetic field lines can cause atomic particles called electrons trapped in the belts to fall into the Earth’s atmosphere at the poles. As the electrons fall into the Earth, they collide with gas molecules in the atmosphere, creating flashes of light in the sky. Each atmospheric gas glows a different color. Oxygen and nitrogen glows red and green and nitrogen glows violet-purple. As these various colors glow and dance in the night sky, they create the Northern Lights and the Southern Lights.
Watching auroras is fun and exciting, but normally you can only see them in places far north like Alaska and Canada. The movement of the aurora across the sky is usually slow enough to easily follow with your eyes but they can also pulsate, flicker, or even move like waves. During solar maximum, auroras are seen as far south as Florida, even Mexico!
Auroras often seem to be very close to the ground, but the lowest aurora is still about 100 kilometers above the ground, a distance much higher than clouds are formed or airplanes can fly. A typical aurora band can be thousands of kilometers long, a few hundred kilometers high, but only a few hundred meters thick.
We hope you are able to travel to far-north places like the Arctic Circle and see the Northern Lights at least once during your lifetime. We know you will never forget it!
scientists這個線索詞連同其近義詞或詞義相關(guān)詞均沒有在文章中出現(xiàn)，因此判斷該問題句的內(nèi)容在文章中沒有被提到。
4. The auroras（極光） are formed （被形成）when the electrons （電子）falling into （落入，陷入）the Earth’s atmosphere（大氣層） at the poles （桿，極地）and colliding with （與...相沖突）gas molecules（氣體分子） in the atmosphere.
A. right B. wrong C. not mentioned
4．A． 細(xì)節(jié)題。利用問題句中的特征詞（ the Earth’s atmosphere ）及細(xì)節(jié)信息詞(auroras，electrons， poles，gas molecules ) 共同作為答案線索， 在文章中查找答案相關(guān)句：
（第2題答案相關(guān)句）The solar wind constantly streams toward the Earth, but don’t worry because a protective magnetic fields surrounds our planet. The same magnetic field that makes your compass point north also steers the particles from the Sun to the north and south poles. The charged particles become trapped in magnetic belts around the Earth. When a large blast of solar wind crashes into the Earth’s magnetic field first gets squeezed and then the magnetic field lines break and reconnect.
（第4題答案相關(guān)句）The breaking（破壞） and reconnecting（再結(jié)合） of the magnetic field （磁場）lines（線，線路, 航線，繩） can cause atomic particles （原子粒子）called electrons （電子）trapped（被捕獲） in the belts（地帶， 帶子） to fall into （落入）the Earth’s atmosphere （大氣層）at the poles. As（當(dāng)） the electrons（電子） fall into the Earth, they collide with （與...碰撞）gas molecules （氣體分子）in the atmosphere, creating（造成， 創(chuàng)造） flashes（閃現(xiàn)） of light（光）in the sky. Each atmospheric gas（大氣層的氣體） glows （發(fā)光）a different color（顏色）. Oxygen（氧） and nitrogen（氮） glows red and green（綠色） and nitrogen（氮） glows violet-purple（紫羅蘭色）. As these various（各種各樣的） colors （顏色）glow and dance（跳舞） in the night sky, they create（造成） the Northern Lights （北極光）and the Southern Lights（南極光）.
Watching（觀看） auroras （極光）is fun（有趣的， 有趣） and exciting（令人興奮的）, but normally you can only see them in places far north like Alaska and Canada. The movement of the aurora across the sky is usually slow enough to easily follow with your eyes but they can also pulsate, flicker, or even move like waves. During solar maximum, auroras are seen as far south as Florida, even Mexico!
1． 分析文章標(biāo)題：The Northern Lights(北極光)
2．直接解題： 1. The Sun’s gravity（引力） is too (太...而不能...)weak(弱的， 虛弱的) to keep its plasma（等離子體） from （阻止/防止...）flowing（流動） to the Earth.
A. right B. wrong C. not mentioned
1．B． 細(xì)節(jié)題。 利用問題句中的特征詞（the Sun’s gravity, the Earth ）及細(xì)節(jié)信息詞(plasma) 共同作為答案線索， 在文章中查找答案相關(guān)句：
（第一段）The sun is stormy（狂暴的，多暴風(fēng)的） and has it own（自己的） kind of weather（氣候，天氣）. It is so（如此...以至于...） hot（熱的，辣的） and active（活躍的） that even(甚至) the Sun’s gravity （引力）cannot hold （控制）its atmosphere（大體層， 氣氛） in check! Energy（能量） flows away from （從...流出）the Sun toward（向） the Earth in a stream of （以一連串的形式）electrified（帶電的） particles（粒子） that move at speeds （以...的速度）around a million miles per（每） hour（小時）. These particles（粒子） are called（被稱為） plasma, and the stream（流，溪， 一連串） of plasma coming from（來自） the Sun is called the solar wind（太陽風(fēng)）. The more active the Sun, the stronger the solar wind.
第一個答案相關(guān)句說“太陽石如此的熱， 如此的活躍， 以至于太陽的引力無法控制住其大氣層”。根據(jù)第2個答案相關(guān)句可知“等離子體就是來自太陽大氣層”， 由此可見造成太陽不能阻止其大氣層中的等離子體流向地球的主要原因不是太陽引力的問題，而是由于太陽過于活躍， 太熱了。
2. The Earth is quite（相當(dāng)，十分） safe（安全的） with（帶有） a magnetic field （磁場）surrounding（圍繞) it to protect（保護...以防止/避免...） it from the attack(襲擊/攻擊) by the solar wind（太陽風(fēng)）.
A. right B. wrong C. not mentioned 2．A． 細(xì)節(jié)題。問題句說“四周帶有磁場的地球是十分安全的，這個磁場能防止地球受到太陽風(fēng)的攻擊”。 利用問題句中的特征詞（Earth ）及細(xì)節(jié)信息詞(magnetic field, solar wind) 共同作為答案線索， 在文章中查找答案相關(guān)句：
（第一段）The sun is stormy and has it own kind of weather. （第一題答案相關(guān)句）It is so hot and active that even the Sun’s gravity cannot hold its atmosphere in check! Energy flows away from the Sun toward the Earth in a stream of electrified particles that move at speeds around a million miles per hour. These particles are called plasma, and the stream of plasma coming from the Sun is called the solar wind. The more active the Sun, the stronger the solar wind.
The solar wind constantly （不斷地）streams（流） toward the Earth, but don’t worry（擔(dān)心） because（因為） a protective（保護的） magnetic fields surrounds（圍繞） our planet. The same magnetic field that makes your compass point north also steers the particles from the Sun to the north and south poles. The charged particles become trapped in magnetic belts around the Earth. When a large blast of solar wind crashes into the Earth’s magnetic field first gets squeezed and then the magnetic field lines break and reconnect.
(以下為第二十四講內(nèi)容) 3. Some scientists（科學(xué)家） are worrying about （正在擔(dān)心 ）the possible （可能的）disappearance（消失） of the Earth’s protective（保護的） magnetic field （磁場）in the future（將來）.
A. right B. wrong C. not mentioned
3．C． 細(xì)節(jié)題。利用問題句中的特征詞（ the Earth ）及細(xì)節(jié)信息詞(scientists, magnetic field) 共同作為答案線索， 在文章中查找答案相關(guān)句：順著上一題的答案位置往下查找答案相關(guān)句：scientists這個線索詞連同其近義詞或詞義相關(guān)詞，這樣的信息也沒有在文章中出現(xiàn)，因此判斷該問題句的內(nèi)容在文章中沒有被提到。
(第2題的答案相關(guān)句) The solar wind constantly streams toward the Earth, but don’t worry because a protective magnetic fields surrounds our planet. The same magnetic field that makes your compass point north also steers the particles from the Sun to the north and south poles. The charged particles become trapped in magnetic belts around the Earth. When a large blast of solar wind crashes into the Earth’s magnetic field first gets squeezed and then the magnetic field lines break and reconnect.
The breaking and reconnecting of the magnetic field lines can cause atomic particles called electrons trapped in the belts to fall into the Earth’s atmosphere at the poles. As the electrons fall into the Earth, they collide with gas molecules in the atmosphere, creating flashes of light in the sky. Each atmospheric gas glows a different color. Oxygen and nitrogen glows red and green and nitrogen glows violet-purple. As these various colors glow and dance in the night sky, they create the Northern Lights and the Southern Lights.
Watching auroras is fun and exciting, but normally you can only see them in places far north like Alaska and Canada. The movement of the aurora across the sky is usually slow enough to easily follow with your eyes but they can also pulsate, flicker, or even move like waves. During solar maximum, auroras are seen as far south as Florida, even Mexico!
Auroras often seem to be very close to the ground, but the lowest aurora is still about 100 kilometers above the ground, a distance much higher than clouds are formed or airplanes can fly. A typical aurora band can be thousands of kilometers long, a few hundred kilometers high, but only a few hundred meters thick.
We hope you are able to travel to far-north places like the Arctic Circle and see the Northern Lights at least once during your lifetime. We know you will never forget it!
scientists這個線索詞連同其近義詞或詞義相關(guān)詞均沒有在文章中出現(xiàn)，因此判斷該問題句的內(nèi)容在文章中沒有被提到。
4. The auroras（極光） are formed （被形成）when the electrons （電子）falling into （落入，陷入）the Earth’s atmosphere（大氣層） at the poles （桿，極地）and colliding with （與...相沖突）gas molecules（氣體分子） in the atmosphere.
A. right B. wrong C. not mentioned
4．A． 細(xì)節(jié)題。利用問題句中的特征詞（ the Earth’s atmosphere ）及細(xì)節(jié)信息詞(auroras，electrons， poles，gas molecules ) 共同作為答案線索， 在文章中查找答案相關(guān)句：
（第2題答案相關(guān)句）The solar wind constantly streams toward the Earth, but don’t worry because a protective magnetic fields surrounds our planet. The same magnetic field that makes your compass point north also steers the particles from the Sun to the north and south poles. The charged particles become trapped in magnetic belts around the Earth. When a large blast of solar wind crashes into the Earth’s magnetic field first gets squeezed and then the magnetic field lines break and reconnect.
（第4題答案相關(guān)句）The breaking（破壞） and reconnecting（再結(jié)合） of the magnetic field （磁場）lines（線，線路, 航線，繩） can cause atomic particles （原子粒子）called electrons （電子）trapped（被捕獲） in the belts（地帶， 帶子） to fall into （落入）the Earth’s atmosphere （大氣層）at the poles. As（當(dāng)） the electrons（電子） fall into the Earth, they collide with （與...碰撞）gas molecules （氣體分子）in the atmosphere, creating（造成， 創(chuàng)造） flashes（閃現(xiàn)） of light（光）in the sky. Each atmospheric gas（大氣層的氣體） glows （發(fā)光）a different color（顏色）. Oxygen（氧） and nitrogen（氮） glows red and green（綠色） and nitrogen（氮） glows violet-purple（紫羅蘭色）. As these various（各種各樣的） colors （顏色）glow and dance（跳舞） in the night sky, they create（造成） the Northern Lights （北極光）and the Southern Lights（南極光）.
Watching（觀看） auroras （極光）is fun（有趣的， 有趣） and exciting（令人興奮的）, but normally you can only see them in places far north like Alaska and Canada. The movement of the aurora across the sky is usually slow enough to easily follow with your eyes but they can also pulsate, flicker, or even move like waves. During solar maximum, auroras are seen as far south as Florida, even Mexico!