跟读练习: Two Different Things Are Killing Sharks - 通过视频学习英语口语

选择练习模式

每种模式都会打开全屏练习室。

101 句

如果句子过短或过长，请点击 Edit 进行调整。

People tend to think of sharks as fearsome, powerful, untouchable predators.

They're definitely scary and powerful, but… untouchable?

Maybe not as much as you might imagine.

Even the white shark, often considered the largest predatory fish on the planet, is not immune to the unforgiving nature of, well, nature.

These iconic predators of the sea face all kinds of threats.

And in two different places, for two apparently different reasons, great whites are dying in large numbers.

And scientists aren't totally sure why.

First, let's introduce the Great White Shark, also known as the White Pointer, or just simply the White Shark.

They were named for their white undersides, despite the fact that most of the shark is actually gray.

White sharks are common in popular media.

And why wouldn't they be?

They grow to around 4 .5 meters long and roughly 1 ,800 kilograms.

And who doesn't love a massive predator?

They also make pretty compelling subjects for lots of scientific research, and they can be easier to study than other sharks.

See, studying migratory species is extremely hard.

They spend time far offshore and in deep waters that are really hard to reach.

But even though white sharks are also migratory, their patterns can be pretty predictable,

and they tend to spend a lot of their time close to beaches and in shallower waters when they're not crossing oceans.

Bad news if you're a seal.

But if you're a researcher, this makes your job way easier.

And the truth is, sharks, including the white shark, are critical to the health of our ocean ecosystems.

They help regulate the population sizes and behaviors of animals at lower trophic levels, such as sea lions and otters.

So if we want a healthy ocean, and therefore a healthy planet, we want healthy sharks.

Which is where our problem lies.

Let's start with South Africa.

White sharks are ubiquitous in South African waters, aggregating in several regions around the coast.

Or, at least, they used to be.

Over the past decade, people have seen fewer white sharks swimming in those waters, and more of them washing up on beaches.

Beached shark carcasses were often found with missing livers and perfect slashes on them, so precise and clean they almost seemed surgical.

Which probably raised more questions than it answered.

And some people were worried that swordfish had evolved into scalpel fish.

But the discovery of tooth marks on the bodies led scientists to a more feasible hypothesis — orcas.

Although we often describe white sharks as if they're the top of the food chain, that's not always the case.

Orcas are known to hunt white sharks, and they're not interested in a filet -o -shark.

They really just want the shark's liver.

Shark livers are massive, making up approximately a third of their body weight.

They're filled with lipids, and since sharks don't have gas -filled swim bladders like their bony fish cousins,

this fatty liver is what they rely on for buoyancy regulation.

Because of how fatty and nutrient -dense shark livers are, it's the perfect meal for a fast -paced, warm -blooded predator like the killer whale.

Orcas have been known to hunt white sharks in other regions, like California.

And when an orca pod rolls through, the sharks start to roll out, avoiding their predators like any sensible prey would.

However, while the new snacking habits of South African orcas sounds like a tidy answer,

it may not be the only reason the number of white sharks has dipped in the last few years.

In addition to orca gains, South African white sharks are also dealing with fishing pressure and shark deterrent efforts on local beaches.

While experts really aren't sure which factor tipped the shark scales, it all adds up to a pretty hostile environment.

Experts hope that addressing as many of these concerns as possible may bring back the iconic

South African sharks.

Not sure how they'll convince the orcas to lay off the liver, but we'll see what happens.

Our next group of endangered white sharks is found off the coast of North America.

And what's disrupting the sharks in Canada and the US is even more confusing

and less visible than it is in South Africa.

Allow me to explain.

In 2023, a dead white shark washed ashore on Prince Edward Island in Canada.

It didn't look injured and seemed otherwise pretty healthy.

But when researchers did a necropsy, which is just an animal autopsy, they found that the shark had inflammation of the brain and surrounding tissues,

otherwise known as meningoencephalitis.

Meanwhile, more seemingly healthy sharks were washing up dead, blood, many with brain swelling.

One shark was seen displaying some odd behavior, like swimming erratically and bumping into things before dying and washing onto a beach.

Surely this was another case of brain inflammation, right?

Shockingly, no. Just when we think we've figured out a pattern, good ol' Mother Nature throws a curveball.

And it's not just the Great Whites.

Dead sharks with swollen brains seemed to be on the rise in several species, like sandbar sharks and thresher sharks.

Even stranger, this is happening in the Atlantic and the Pacific, meaning whatever the problem is, it's really widespread.

So, some mysterious thing is causing sharks' brains to swell up and die, and we still don't know exactly what.

But, as it turns out, the answer may be hidden in a bunch of decades -old frozen salmon sharks.

In the early 2000s, 18 beached salmon sharks were found to have died of meningoencephalitis.

And in 2012, researchers analyzed some of them and found that a type of bacterium called

Carnobacterium malta rheumaticum was the likeliest culprit.

Which was weird, because this bacterium has been found in other fish species and in the water they swim in.

And those guys all have perfectly unswollen brains.

But for some unknown reason, this bacterium may be becoming pathogenic in some fish, including sharks.

And we have an idea of how it could be reaching their brains.

Through the endolymphatic system, which aids in hearing, balance, and orientation.

Sharks have small pores on their heads that lead to their endolymphatic ducts, which provide access to the cranium.

And we know that when these structures get invaded by pathogens in the water,

it can cause disease and even death in several shark and ray species.

So what do we know?

We know that, for a decade, sharks have been washing up on beaches.

We know that their deaths are often caused or accompanied by meningoencephalitis.

And we know that this disease is sometimes attributed to a particular bacterium.

What we don't know is probably the biggest piece of this medically mysterious marine puzzle,

which is why this is happening and how concerned we all should be about it.

Scientists are worried for some reasons and not so worried for others.

Seeing sharks wash up on shore doesn't seem like it could be positive in any way,

but it could be a sign that shark populations are recovering.

A bigger population of sharks that are living also means there's a bigger population of sharks that are dying, hence an increase in washed up carcasses.

And if this thing is contagious, more sharks also means more of a chance for diseases to be passed around,

simply because the population is bigger and might be more densely packed into an area.

So while we don't love a disease, if it means that shark populations are rebounding, it's not all bad.

The concern comes in though

when we start to think about a bacteria that's been living on other fish species without a problem, suddenly becoming a deadly pathogen in sharks.

If this truly is what is happening, we need to understand why.

Is it climate change?

Pollution?

Or a secret third option?

Knowing what causes the bacterium to go rogue can help us figure out how to stop it from spreading

and prevent it from happening with other bacteria in the future.

These two shark -killing mysteries have two different causes, and therefore two different solutions, at least.

But that also means they're teaching us two different lessons about our planet, our oceans, and all the big and not so big creatures in them,

100

from the sharks and the orcas down to tiny bacteria.

101

And maybe the biggest one is that the driving force behind ecosystem shifts is never really black and white.

下载应用

流利口语所需的一切

AI 发音评分逐句打分

音标练习掌握每个音

词汇学习建立你的词库

词汇游戏边玩边学

扫码

Download on theApp Store Get it onGoogle Play

同频道

FOR YOU

本课的词汇与口语要点

这节口语课以视频“Two Different Things Are Killing Sharks”为素材。视频中反复出现的词有：shark, orca, brain, liver, fish。这段视频共有 101 个句子、1404 个单词可供跟读。讲话部分时长为 7:32。说话人语速较快，每分钟约 186 个词，会出现较多连读和弱读。只有 77% 的单词属于英语最常用的 3,000 词，词汇难度较高。

视频中的重点词汇

视频中 15 个值得学习的单词，附发音和释义：

单词	发音	释义
wash 动词	/wɑʃ/	洗, 洗滌 /洗涤
predator 名词	/ˈpɹɛd.ə.tɚ/	掠食者, 天敵 /天敌
swim 动词	/swɪm/	游泳
scientist 名词	/ˈsaɪəntəst/	科學家 /科学家
liver 名词	/ˈlɪvɚ/	肝, 肝臟 /肝脏
researcher 名词	/ˈɹiˌsɝ.t͡ʃɚ/	研究員 /研究员, 研究者
swell 动词	/swɛl/	膨脹 /膨胀, 擴大 /扩大
mysterious 形容词	/mɪˈstɪɹi.əs/	神秘, 來源不明的 /来源不明的
iconic 形容词	/aɪˈkɑnɪk/	代表性的
ecosystem 名词	/ˈikoʊˌsɪstəm/	生態系 /生态系, 生態系統 /生态系统
inflammation 名词	/ɪnfləˈmeɪ̯ʃən/	炎症, 發炎 /发炎
meal 名词	/ˈmiːl/	餐, 飯 /饭
meanwhile 副词	/ˈmiːnwaɪl/	同時 /同时
killer 名词	/ˈkɪlɚ/	殺手 /杀手, 兇手 /凶手
lesson 名词	/ˈlɛs.ən/	課業 /课业, -課 /-课

视频中出现的短语动词

单词	发音	释义
figure out 动词		弄清楚
wash up 动词		洗臉 /洗脸, 洗手
make up 动词	/ˌmeɪk ˈʌp/	組成 /组成
turn out 动词		原來 /原来

视频中的语法

说话人最常用的结构，并附上视频中的原话：

结构	视频中的用法
现在完成进行时 have/has been + -ing — 以前开始、现在仍在继续的动作	have been washing · that's been living
被动语态 be + 过去分词 — 强调发生了什么，而不是谁做的	were named · were often found · are known
现在完成时 have/has + 过去分词 — 过去发生但与现在仍有关联的事	have seen · have been known · has dipped

需要注意的发音

说话人用了 21 次缩略和弱读形式，例如 they're, don't, aren't。请按听到的简短形式来说。

“th” 音: tooth /tuθ/, hypothesis /haɪˈpɒθɪsɪs/, pathogen /ˈpæθəd͡ʒn̩/, pathogenic /pæθəˈd͡ʒɛnɪk/, thresher /ˈθɹɛʃə(ɹ)/
“sh” 和 “zh” 音: wash /wɑʃ/, inflammation /ɪnfləˈmeɪ̯ʃən/, regulation /ˌɹɛɡjʊˈleɪʃən/, shore /ʃɔɹ/, tissue /ˈtɪʃ.(j)u/
长单词——注意重音位置: mysterious /mɪˈstɪɹi.əs/, ecosystem /ˈikoʊˌsɪstəm/, inflammation /ɪnfləˈmeɪ̯ʃən/, regulation /ˌɹɛɡjʊˈleɪʃən/, orientation /ˌɔː.ɹi.ənˈteɪ.ʃən/

中文母语者容易读错的音：

/v/ — 不要读成 /w/，上齿轻触下唇: liver /ˈlɪvɚ/, discovery /dɪˈskʌv.ɹi/, visible /ˈvɪzɪb(ə)l/, recover /ɹɪˈkʌvɚ/, convince /kənˈvɪns/
词尾辅音 — 要读清楚，后面不要加元音: wash /wɑʃ/, scientist /ˈsaɪəntəst/, mysterious /mɪˈstɪɹi.əs/, iconic /aɪˈkɑnɪk/, hence /ˈhɛns/
/r/ 和 /l/ 的区别: regulation /ˌɹɛɡjʊˈleɪʃən/, roughly /ˈɹʌf.li/, rely /ɹɪˈlaɪ/, regulate /ˈɹɛɡ.jə.leɪt/, predictable /pɹəˈdɪktəbləl/

如何用这段视频练习

先完整听一遍视频，不要开口，记下不认识的单词。
先用 0.75 倍速逐句跟读，熟练之后再回到正常速度。
录下自己的声音并与原声对比，特别注意 wash, predator, swim 这类单词。

什么是跟读法？

跟读法 (Shadowing) 是一种有科学依据的语言学习技巧，最初开发用于专业口译员的培训，并由多语言者Alexander Arguelles博士普及。这个方法简单而强大：您在听英语母语原声的同时立即大声重复——就像是一个延迟1-2秒紧跟说话者的影子。与被动听力或语法练习不同，跟读法强迫您的大脑和口腔肌肉同时处理并模仿真实的讲话模式。研究表明它能显着提高发音准确性，语调，节奏，连读，听力理解和口语流利度——使其成为雅思口语备考和真实英语交流最有效的方法之一。

影子跟读法: 阅读完整分步指南 →

跟读练习: Two Different Things Are Killing Sharks - 通过视频学习英语口语

选择练习模式

下载应用

同频道

What’s Ruining Our Ruins?

Why Do We Sneeze?

The Science Behind The Odyssey's Greatest Challenge

Do Penguins Control the Weather?

The Most Important Picture in the History of Science

Why Can’t We Have Unicorns?

Does Aloe Really Treat a Sunburn?

What's Really Behind The Adderall Shortage?

Ticks Can Spread An Allergy To… Red Meat?

The ONE Disease That Smoking Can Help Treat

How Onions ACTUALLY Make You Cry (And How to Stop Them)

推荐视频

Why no aquarium has a great white shark

You Will Only Like Half of This Video

What is a Keystone Species? - Wild Education

Why The Entire Ocean Is Terrified of Sperm Whales

The Most Dangerous Woman in Science Says We Got the Dinosaur Extinction Totally Wrong

Why did white men conquer the world?

English lesson

READING EXPLORER 2 Unit 6B THE TRUTH ABOUT GREAT WHITES

What Would Happen If an Asteroid Hit the Ocean?

Before We Became the Last Humans:The Lost Species That Once Shared Our World|Prehistoric Documentary

The Most Dangerous Animal

The REAL reason China built so much