五、(原版外刊)阅读理解。
关于金枪鱼的趣事
Tuna are amazing sea creatures(生物) with many surprising facts. When the water is warmer than 20℃, adult tuna lay millions of eggs and let baby tuna into the ocean.
Life is not easy for baby tuna. Most of the tiny baby fish get eaten by bigger animals. Some young tuna even eat each other! Only 1 out of 30 million baby tuna grows up to be an adult. It takes them four to five years to become mature(成熟的) enough to have their own babies. This tells us how important it is to protect tuna that can reproduce(繁殖).
Spawning is very tiring for tuna. They can lose 20 to 40 kilograms during this time. After spawning, they need to eat fatty food to get strong again. Every year, some recorded tuna swim from the Mediterranean Sea(地中海) to the Oresund. They go there for a big "meal" with lots of food.
Scientists like Jeppesen and Katrine Larsen study tuna. They once saw 300 tuna in one evening—the sea looked like it was boiling! They record when and where they see tuna using their phones. Larsen wants to do a research project on tuna's living habits. Marine biologists(海洋生物学家) still don't know much about tuna, but that's what makes studying them so exciting.
(素材选自 Reader's Digest India)
1. When do adult tuna lay millions of eggs?
A. When the water is colder than 20℃.
B. When the water is warmer than 20℃.
C. After swimming in the Mediterranean Sea.
D. After eating fatty food.
2. Why is it important to protect tuna that can reproduce?
A. Because they are the biggest sea creatures.
B. Because very few baby tuna can grow into adults.
C. Because they lose much weight when spawning.
D. Because scientists want to study their living habits.
3. What does the word "Spawning" probably mean in the passage?
A. Looking for food.
B. Laying eggs.
C. Moving to another place.
D. Growing up.
4. What is the main idea of the passage?
A. How scientists study tuna in the ocean.
B. Why tuna need to eat fatty food after spawning.
C. Some interesting facts about tuna's life and research on them.
D. How tuna swim from the Mediterranean Sea to the Oresund.
关于金枪鱼的趣事
Tuna are amazing sea creatures(生物) with many surprising facts. When the water is warmer than 20℃, adult tuna lay millions of eggs and let baby tuna into the ocean.
Life is not easy for baby tuna. Most of the tiny baby fish get eaten by bigger animals. Some young tuna even eat each other! Only 1 out of 30 million baby tuna grows up to be an adult. It takes them four to five years to become mature(成熟的) enough to have their own babies. This tells us how important it is to protect tuna that can reproduce(繁殖).
Spawning is very tiring for tuna. They can lose 20 to 40 kilograms during this time. After spawning, they need to eat fatty food to get strong again. Every year, some recorded tuna swim from the Mediterranean Sea(地中海) to the Oresund. They go there for a big "meal" with lots of food.
Scientists like Jeppesen and Katrine Larsen study tuna. They once saw 300 tuna in one evening—the sea looked like it was boiling! They record when and where they see tuna using their phones. Larsen wants to do a research project on tuna's living habits. Marine biologists(海洋生物学家) still don't know much about tuna, but that's what makes studying them so exciting.
(素材选自 Reader's Digest India)
1. When do adult tuna lay millions of eggs?
A. When the water is colder than 20℃.
B. When the water is warmer than 20℃.
C. After swimming in the Mediterranean Sea.
D. After eating fatty food.
2. Why is it important to protect tuna that can reproduce?
A. Because they are the biggest sea creatures.
B. Because very few baby tuna can grow into adults.
C. Because they lose much weight when spawning.
D. Because scientists want to study their living habits.
3. What does the word "Spawning" probably mean in the passage?
A. Looking for food.
B. Laying eggs.
C. Moving to another place.
D. Growing up.
4. What is the main idea of the passage?
A. How scientists study tuna in the ocean.
B. Why tuna need to eat fatty food after spawning.
C. Some interesting facts about tuna's life and research on them.
D. How tuna swim from the Mediterranean Sea to the Oresund.
答案：1.B
2.B
3.B
4.C
2.B
3.B
4.C
解析：
【分析】
这是一篇科普类阅读理解题，包含细节理解、词义猜测、主旨大意三类常见题型，解题时遵循"题干划关键词→回原文定位对应内容→比对选项排除错误项"的思路即可：
1. 第一题直接提取题干关键词"adult tuna lay millions of eggs"，回到原文首段找对应描述就能直接得到答案；
2. 第二题定位到题干关键词"protect tuna that can reproduce"所在的第二段，往前找原因，就能发现幼金枪鱼的存活率极低，由此推导保护可繁殖成鱼的原因；
3. 第三题词义猜测题，结合前后文关于金枪鱼繁殖的相关描述，代入选项验证就能推出词义；
4. 第四题主旨大意题，排除只覆盖文章局部内容的片面选项，选出能概括全文内容的答案。
【解析】
1. 细节理解题：根据原文第一段第二句"When the water is warmer than 20℃, adult tuna lay millions of eggs and let baby tuna into the ocean"，可知成年金枪鱼在水温高于20℃时产下数百万枚卵，A选项和原文表述相反，C、D选项描述的事件和产卵时间无关，因此选B。
2. 细节理解题：原文第二段明确说明"Only 1 out of 30 million baby tuna grows up to be an adult. It takes them four to five years to become mature enough to have their own babies"，也就是仅有极少量的幼金枪鱼能顺利长成可繁殖的成鱼，因此保护可繁殖的金枪鱼十分重要，A、C、D都不是对应的原因，因此选B。
3. 词义猜测题：前文一直在介绍金枪鱼产卵繁殖的相关内容，后文提到该过程会让金枪鱼体重下降20到40公斤，结束后需要进食高脂食物恢复体力，完全符合鱼类产卵的特征，因此Spawning的含义是产卵，排除A找食物、C迁徙、D长大的错误选项，选B。
4. 主旨大意题：全文既介绍了金枪鱼产卵习性、幼鱼存活率、觅食迁徙等生活相关的趣事，也介绍了科学家对金枪鱼的相关研究，A、B、D三个选项都只对应文章的局部内容，过于片面，只有C选项能完整概括全文主旨，因此选C。
【答案】
1.B 2.B 3.B 4.C
【知识点】
阅读细节查找，词义猜测，主旨归纳
【点评】
这是一篇难度适中的科普类说明文阅读，大部分题目都可以通过回文定位直接找到对应依据，仅词义猜测和主旨题需要结合上下文逻辑推导，既考察学生的信息定位能力，也能帮助学生拓展海洋生物相关的科普常识，适合巩固基础阅读解题技巧。
【难度系数】
0.85
这是一篇科普类阅读理解题，包含细节理解、词义猜测、主旨大意三类常见题型，解题时遵循"题干划关键词→回原文定位对应内容→比对选项排除错误项"的思路即可：
1. 第一题直接提取题干关键词"adult tuna lay millions of eggs"，回到原文首段找对应描述就能直接得到答案；
2. 第二题定位到题干关键词"protect tuna that can reproduce"所在的第二段，往前找原因，就能发现幼金枪鱼的存活率极低，由此推导保护可繁殖成鱼的原因；
3. 第三题词义猜测题，结合前后文关于金枪鱼繁殖的相关描述，代入选项验证就能推出词义；
4. 第四题主旨大意题，排除只覆盖文章局部内容的片面选项，选出能概括全文内容的答案。
【解析】
1. 细节理解题：根据原文第一段第二句"When the water is warmer than 20℃, adult tuna lay millions of eggs and let baby tuna into the ocean"，可知成年金枪鱼在水温高于20℃时产下数百万枚卵，A选项和原文表述相反，C、D选项描述的事件和产卵时间无关，因此选B。
2. 细节理解题：原文第二段明确说明"Only 1 out of 30 million baby tuna grows up to be an adult. It takes them four to five years to become mature enough to have their own babies"，也就是仅有极少量的幼金枪鱼能顺利长成可繁殖的成鱼，因此保护可繁殖的金枪鱼十分重要，A、C、D都不是对应的原因，因此选B。
3. 词义猜测题：前文一直在介绍金枪鱼产卵繁殖的相关内容，后文提到该过程会让金枪鱼体重下降20到40公斤，结束后需要进食高脂食物恢复体力，完全符合鱼类产卵的特征，因此Spawning的含义是产卵，排除A找食物、C迁徙、D长大的错误选项，选B。
4. 主旨大意题：全文既介绍了金枪鱼产卵习性、幼鱼存活率、觅食迁徙等生活相关的趣事，也介绍了科学家对金枪鱼的相关研究，A、B、D三个选项都只对应文章的局部内容，过于片面，只有C选项能完整概括全文主旨，因此选C。
【答案】
1.B 2.B 3.B 4.C
【知识点】
阅读细节查找，词义猜测，主旨归纳
【点评】
这是一篇难度适中的科普类说明文阅读，大部分题目都可以通过回文定位直接找到对应依据，仅词义猜测和主旨题需要结合上下文逻辑推导，既考察学生的信息定位能力，也能帮助学生拓展海洋生物相关的科普常识，适合巩固基础阅读解题技巧。
【难度系数】
0.85