Learn how mosquitoes use six needles to suck your blood.
It is important to read the vocabulary before you watch the video. This will improve your ability to understand the video. It will also help you understand how the new vocabulary is used naturally.
The first time you watch the video, just try to understand the overall situation.
First try to answer all the questions from memory. Then rewatch the video and try to answer the questions that you missed.
Watch the video again while you read the script. Reading and listening at the same time will help you hear each individual word and improve your listening accuracy.
There are several different activities that focus on test preparation, vocabulary, grammar, and sentence structure.
Es importante leer el vocabulario antes de ver el video. Esto mejorará su capacidad para comprender el video. También le ayudará a comprender cómo se usa el nuevo vocabulario de forma natural.
La primera vez que vea el video, intente comprender la situación general.
Primero intente responder todas las preguntas de memoria. Luego, vuelva a ver el video e intente responder las preguntas que se perdió.
Mire el video nuevamente mientras lee el guión. Leer y escuchar al mismo tiempo lo ayudará a escuchar cada palabra individual y mejorará su precisión auditiva.
Hay una serie de actividades diferentes que se centran en la preparación de la examen, el vocabulario, la gramática y la estructura de las oraciones.
비디오를 보기 전에 어휘와 배경을 읽는 것이 중요합니다. 이렇게 하면 비디오를 이해하는 능력이 향상됩니다. 또한 새로운 어휘가 어떻게 자연스럽게 사용되는지 이해하는데 도움이됩니다.
비디오를 처음 볼 때 전체 상황을 이해하려고 노력하세요.
먼저 모든 질문에 답을 해보세요. 그런 다음 비디오를 다시보고 놓친 질문에 답해보세요.
대본을 읽는 동안 비디오를 다시 보세요. 읽기와 듣기를 동시에 하면 각각의 단어를 듣고, 듣기 정확도를 향상시킬 수 있습니다.
듣기 정확도, 발음, 어휘, 문법 및 문장 구조에 초점을 맞춘 다양한 액티비티가 있습니다.
É importante ler o vocabulário antes de assistir ao vídeo. Isso melhorará sua capacidade de entender o vídeo. Também ajudará você a entender como o novo vocabulário é usado naturalmente.
Na primeira vez que assistir ao vídeo, tente entender a situação geral.
Primeiro, tente responder a todas as perguntas de memória. Em seguida, assista novamente ao vídeo e tente responder às perguntas que você errou.
Assista ao vídeo novamente enquanto lê o roteiro. Ler e ouvir ao mesmo tempo ajudará você a ouvir cada palavra individualmente e a melhorar sua precisão auditiva.
Existem várias atividades diferentes que se concentram na preparação para o teste, vocabulário, gramática e estrutura de frases.
[n] - noun, [v] - verb, [phv] - phrasal verb, [adj] - adjective, [exp] - expression
Questions
These are guided listening questions. These questions are NOT designed to test or trick you. They are designed to guide you through the video.
TIP: If you don’t understand something in the video, click "Show Answers". You should be able to understand all of the important points of the video by reading the questions and the correct answers.
Preguntas
Estas son preguntas de escucha guiada. Estas preguntas NO están diseñadas para ponerte a prueba o engañarte. Están diseñados para guiarlo a través del video.
CONSEJO: Si no entiende algo en el video, haga clic en "Show Answers". Debería poder comprender todos los puntos importantes del video leyendo las preguntas y las respuestas correctas.
질문
이것은 안내식 듣기 질문입니다. 이 질문들은 당신을 시험하거나 속이기 위한 것이 아닙니다. 동영상을 통해 안내하도록 설계되었습니다.
팁 : 동영상에서 이해가 되지 않는 부분이 있으면 "Show Answers"를 클릭하세요. 질문과 정답을 읽으면서 영상의 중요한 요점을 모두 이해할 수 있어야 합니다.
Perguntas
Estas são perguntas de escuta guiadas. Essas perguntas NÃO foram elaboradas para testar ou enganar você. Eles são projetados para guiá-lo através do vídeo.
DICA: Se você não entender algo no vídeo, clique em "Mostrar respostas". Você deve entender todos os pontos importantes do vídeo lendo as perguntas e as respostas corretas.
This is the deadliest animal in the world. Mosquitoes kill hundreds of thousands of people each year. The most vulnerable people: children,
pregnant women... No other bite kills more humans or makes more of us sick.
So what makes a mosquito’s bite so effective? For starters, they’re motivated. Only females bite us. They need blood to make eggs and a pool
of water for their babies to hatch in. Even a piece of trash can hold enough.
At first glance, it looks simple. This mosquito digging her proboscis into us. But the tools she’s using here are sophisticated. First, a
protective sheath retracts. See it bending back?
If you look at a mosquito’s head under a microscope, you can see what that sheath protects. And inside, there are six needles!
Two of them have tiny teeth. She uses those to saw through the skin. They’re so sharp you can barely feel her pushing.
These other two needles hold the tissues apart while she works.
From under the skin, you can see her probing, looking for a blood vessel. Receptors on the tip of one of her other needles pick up on chemicals
that our blood vessels exude naturally and guide her to it. Then she uses this same needle like a straw.
As her gut fills up, she separates water from the blood and squeezes it out. See that drop? That frees up space to stuff herself with more nutritious
red blood cells
With another needle, she spits chemicals into us. They get our blood flowing more easily, and give us itchy welts afterwards.
And sometimes, before she pries herself away, she leaves a parting gift in her saliva: a virus or a parasite that can sicken or kill us. There’s
nothing in it for her. The viruses and parasites are just hitching a ride. But this is what makes mortal enemies out of us and mosquitoes.
They take our blood. Sometimes we take theirs. But often, not soon enough.
Good. You’re still there. These are the larvae of Culex pipiens, a.k.a. the common house mosquito here in California. Gross, right? Well, you can avoid
them by emptying your rain gutters. Pet water dishes too.
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