五、新素材 可以改变性别的鱼 阅读理解
你知道神仙鱼吗? 它可以改变性别。让我们一起来了解一下吧。
词数: 201 体裁: 说明文 核心素养: 思维品质
话题: 黑斑神仙鱼 难度: 中 建议用时: 5 分钟
There is a fish called the black spot angelfish, which can change from female(雌性) to male(雄性). No, it cannot do it by simply wishing to become male. The change happens for a specific reason.
The angelfish live in groups. And each group has one male fish, which is blue in colour, and four female fish, which are yellow in colour.
The male angelfish is the strongest and largest member of the group. He is the one who protects and looks after the females and acts like their "safety guard". When the male dies, the group needs a "safety guard". This is when the largest female fish in the group begins to change its appearance.
She begins to grow larger in size. After a week, she starts changing colour, from yellow to blue. Slowly, the changes take place. She begins behaving like a male. Two weeks later, black spots appear on her body. This shows that the change is complete. She is now completely male!
Another interesting fact about angelfish is that they make a special living in the fish world. Most of them act as "cleaners" for other fish. They pick parasites (寄生物) and dead things from the body of other fish.
1. There are fish in each group of angelfish.
A. 2
B. 3
C. 4
D. 5
2. The male angelfish is the member of the group.
A. longest
B. most beautiful
C. oldest
D. strongest and largest
3. It takes angelfish week(s) to change from female to male completely.
A. one
B. two
C. three
D. four
4. The angelfish feed on .
A. grass
B. small fish
C. the sand
D. parasites and dead things

五、[文章大意]本文介绍了一种可以改变自己性别的鱼。它们过着群居生活,当群里唯一的雄性鱼死去的时候,群里最大的雌性鱼就会变为雄性。
1. D [解析]细节理解题。根据第二段第二句“And each group has one male fish, which is blue in colour, and four female fish, which are yellow in colour.”可知,每个鱼群有一条雄性鱼和四条雌性鱼组成,故一共是五条鱼。故选 D。
2. D [解析]细节理解题。根据第三段第一句“The male angelfish is the strongest and largest member of the group.”可知,雄性鱼在鱼群中是最强壮且最大的鱼。故选 D。
3. C [解析]细节理解题。根据第四段可知,完成变性的过程需要三周的时间。故选 C。
4. D [解析]细节理解题。根据最后一段最后一句“They pick parasites(寄生物) and dead things from the body of other fish.”可知,这种鱼啄食其他鱼身上的寄生物和坏死的东西。故选 D。

【分析】
做这类阅读理解细节题时，需先明确题干关键词，再回到原文定位相关语句，将选项与原文内容逐一比对，从而选出正确答案。需针对每道题的关键词（如“each group”“male angelfish”等）精准定位原文对应内容，避免错选。
【解析】
1. 细节理解题。根据原文第二段第二句“And each group has one male fish, which is blue in colour, and four female fish, which are yellow in colour.”可知，每个鱼群有1条雄性鱼和4条雌性鱼，共5条，故选D。
2. 细节理解题。根据原文第三段第一句“The male angelfish is the strongest and largest member of the group.”可知，雄性神仙鱼是鱼群中最强壮且最大的成员，故选D。
3. 细节理解题。根据原文第四段：雌性鱼先变大，一周后开始变色，两周后黑斑出现、变性完成，总耗时三周，故选C。
4. 细节理解题。根据原文最后一段最后一句“They pick parasites(寄生物) and dead things from the body of other fish.”可知，神仙鱼以寄生物和坏死物质为食，故选D。
【答案】1.D 2.D 3.C 4.D
【知识点】阅读理解细节理解、说明文阅读
【点评】本文围绕可变性别的神仙鱼展开说明，考查学生提取原文细节信息的能力，题目难度中等，只要仔细阅读原文定位关键语句即可正确作答。
【难度系数】0.6