Zebrafish, named for their characteristic stripes, have been a popular test subject for researchers. Only a few centimeters in length, the fish breed easily in captivity, grow quickly, and their transparent body makes it easy to study their organs. Above all, they possess some amazing “self-healing” power. When part of their heart is removed, they can grow it back in a matter of weeks. When blinded, they can quickly regain the ability to see.
Recent studies show that humans and zebrafish have the same major organs and share 70 percent of the genes. Moreover, 84 percent of human genes associated with disease find a counterpart in zebrafish. Scientists thus hope that understanding the self-healing mystery of the fish may one day allow humans to regenerate such organs as eyes, hearts, and spines.
Researchers at Vanderbilt University are particularly interested in zebrafish retina regeneration. They have learned that damage of retina can cause blindness in zebrafish, yet it only takes about three to four weeks before vision is restored. The structure and cell types of zebrafish retinas are almost identical to those of humans. If the process can be replicated in humans, it may give rise to new treatments for blindness caused by retinal damage.
In order to know exactly how zebrafish retina is regenerated, the team looked at the neurotransmitter gamma-aminobutyric acid (GABA), a chemical messenger in the brain that reduces the activity of neurons. They found that lowering GABA levels in zebrafish can trigger retina regeneration, while a high level of GABA concentration will suppress the regeneration process. This suggested that GABA plays an important role in the fish's ability to regain their sight.
The team is beginning to test the GABA theory on mice. If that works, human trials will be next on the agenda. If the research proves successful in humans, some of the nearly 40 million blind people worldwide may one day have a tiny, striped fish to thank.
43. What can we learn about zebrafish from the passage?
(A) How they should be studied in labs.
(B) Where they derive their regenerative ability.
(C) Why they share humans' genetic code.
(D) What they may offer in medical advancements.
44. Which of the following statements is true regarding GABA in zebrafish?(A) Increasing GABA level facilitates neuron activities.
(B) There is a high level of GABA in the brain of zebrafish.
(C) Lowering GABA levels in the brain can stimulate retina regrowth.
(D) GABA contains chemical elements that trigger the growth of neurons.
45. Which of the following is closest in meaning to “replicated” in the third paragraph?
(A) Reproduced. (B) Reassembled. (C) Recycled. (D) Restored.
46. According to the passage, which of the following is an opinion, but NOT a fact?
(A) Humans and zebrafish have 70 percent of genes in common.
(B) Zebrafish can quickly recover vision after damage to the retina.
(C) Scientists are testing if the GABA theory works on mice as it does on zebrafish.
(D) Understanding regeneration in zebrafish may allow humans to regrow their organs.
43.D 44. C 45. A 46. D
第一段第一句
Zebrafish, named for their characteristic stripes, have been a popular test subject for researchers.
斑馬魚，因其典型特有的條紋而得名，一直是研究人員常用的測試對象。
💡主旨： 斑馬魚常用於研究
🔍找主詞和動詞
主詞： zebrafish，fish 的單複數同型
動詞：have been （故主詞是複數）
🚫排除干擾：為什麼 named 不是動詞？
named： 主詞和動詞之間不會無故加逗號，所以 named 不可能當 zebrafish 的動詞。
🧩長句解析：拆解與組裝
🪛拆解 本句可拆為兩個簡單句
第一句（核心句）Zebrafish have been a popular test subject for researchers.
第二句（名稱來源）Zebrafish are named for their characteristic stripes.
🧵組裝
Step 1. 把第二句改成核心句 zebrafish 的關係子句：把第二句的 zebrafish 改成 which，後嫁接在第一句的 zebrafish 之後
Zebrafish which are named for their characteristic stripes have been a popular test subject for researchers.
Step 2. 進一步加逗號隔開子句與核心句，成為非限定用法：子句只是補充說明，不是額外限制特定 zebrafish ，故需使用非限定用法
Zebrafish, which are named for their characteristic stripes, have been a popular test subject for researchers.
Step 3. 關係子句的省略：省略 which，及被動語態動詞中的 be-V，即 are
Zebrafish, which are named for their characteristic stripes, have been a popular test subject for researchers.
🎈深度比較：關係子句的 限定 vs. 非限定 用法
透過 Elon Musk（馬斯克）和 who cofounded 7 companies ，可理解逗號的威力：
限定用法（無逗號）：
Elon Musk is a South African–born American entrepreneur who cofounded 7 companies.
說明：Elon Musk 是創辦了 7 間公司的南非出生企業家，而非任何南非出生企業家，故需用子句限定範圍（無逗號）。
非限定用法（有逗號）：
Elon Musk, who cofounded 7 companies, is the world's richest person now.
說明：大家都知道 Elon Musk 是誰。有無此子句無所謂（有逗號）。
第一段第二句
Only a few centimeters in length, the fish breed easily in captivity, grow quickly, and their transparent body makes it easy to study their organs.
它們只有幾公分長，在人工飼養下容易繁殖，生長迅速，而且透明的身體讓人易於研究它們的器官。
💡主旨：斑馬魚的特徵使得它們易於被用於研究
🔍找主詞和動詞
本句有兩個核心句，以 and 連接
第一句
主詞： fish
動詞： breed 和 grow。
第二句
主詞：body
動詞：makes
🚫排除干擾：為什麼它們不是動詞？
to study：不定詞，不能當動詞。
🍃片語 in captivity 意為［關押囚禁的狀態］。
🦚句型解析 their transparent body makes it easy to study their organs
此處 it 是 make 的 虛受詞，真受詞是 to study their organs
📢 重要規則：當動詞是 以不定詞 (to-V原型) 或 that 子句 當受詞，且後面接補語時， 必須先用 虛受詞 it
即it + 補語 + to-V原型/that子句。
🛋️ Eating healthy makes it easy to lose weight.
I find it fun to learn English.
I find it strange that she didn't call.
I think it true that he is honest.
I consider it a crime to drive drunk.
You should keep it clear that you are the boss.
💞 若將 不定詞 改為 V-ing，則可不必使用該規則，但若 補語 超過 一個字，則使用不定詞及上述規則，使文句較順暢優美
🛋️不太順暢的句子
We consider serving you an honor. 補語是 an honor，超過一個字
正確且自然的句子
Eating healthy makes losing weight easy.
I consider living here expensive.
We consider hiring him risky.
本文包含作者多年累積的英文學習認知與教學精華。內容受著作權法保護，僅供付費讀者個人學習使用。嚴禁將教學內容、例句、講義圖表轉載至公開社群或用於商業教學（如補習班教材）。感謝您支持原創教學內容。
🧩長句解析：拆解與組裝
🪛拆解 本句可拆為四個簡單句
第一句（體型）The fish are only a few centimeters in length.
第二句（核心句 1）The fish breed easily in captivity.
第三句（核心句 2）The fish grow quickly.
第四句 (核心句 3）Their transparent body makes it easy to study their organs.
🧵組裝
Step 1. 將第一句以分詞構句的方式與核心句1 合併，置於句首： 由於主詞與核心句的主詞相同，省略之， be-V 亦省略，並須以逗號格開，
The fish are Only a few centimeters in length, the fish breed easily in captivity.
Step 2. 以連接詞 and 連接 Step 1 的結果 與核心句2：兩者主詞相同，連接後可省略核心句2 的主詞The fish are Only a few centimeters in length, the fish breed easily in captivity, and The fish grow quickly.
Step 3. 再以and 連接 Step 2 的結果 與核心句3：The fish are Only a few centimeters in length, the fish breed easily in captivity, and The fish grow quickly, and their transparent body makes it easy to study their organs.
