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Mosquito Bites


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Published: 11.11.2019   [ UPDATED JUN 2025 ]
Level 4   |   Time: 3:17
Accent: American
Source: PBS Deep Look

Learn how mosquitoes use six needles to suck your blood.


triangle Directions 목표 Direcciones Instruções


  1. READ the VOCABULARY

    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.

  2. WATCH the VIDEO

    The first time you watch the video, just try to understand the overall situation.

  3. ANSWER the QUESTIONS

    First try to answer all the questions from memory. Then rewatch the video and try to answer the questions that you missed.

  4. WATCH and READ the SCRIPT

    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.

  5. DO the ACTIVITIES

    There are several different activities that focus on test preparation, vocabulary, grammar, and sentence structure.

  1. LEA el VOCABULARIO

    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.

  2. VER el VIDEO

    La primera vez que vea el video, intente comprender la situación general.

  3. RESPONDE a las PREGUNTAS

    Primero intente responder todas las preguntas de memoria. Luego, vuelva a ver el video e intente responder las preguntas que se perdió.

  4. MIRAR Y LEER

    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.

  5. HACER LAS ACTIVIDADES

    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.

  1. 어휘 읽기

    비디오를 보기 전에 어휘와 배경을 읽는 것이 중요합니다. 이렇게 하면 비디오를 이해하는 능력이 향상됩니다. 또한 새로운 어휘가 어떻게 자연스럽게 사용되는지 이해하는데 도움이됩니다.

  2. 비디오 보기

    비디오를 처음 볼 때 전체 상황을 이해하려고 노력하세요.

  3. 문제에 답하기

    먼저 모든 질문에 답을 해보세요. 그런 다음 비디오를 다시보고 놓친 질문에 답해보세요.

  4. 비디오 보면서 대본 읽기

    대본을 읽는 동안 비디오를 다시 보세요. 읽기와 듣기를 동시에 하면 각각의 단어를 듣고, 듣기 정확도를 향상시킬 수 있습니다.

  5. 액티비티 하기

    듣기 정확도, 발음, 어휘, 문법 및 문장 구조에 초점을 맞춘 다양한 액티비티가 있습니다.

  1. LER o VOCABULÁRIO

    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.

  2. ASSISTA ao VÍDEO

    Na primeira vez que assistir ao vídeo, tente entender a situação geral.

  3. RESPONDA às PERGUNTAS

    Primeiro, tente responder a todas as perguntas de memória. Em seguida, assista novamente ao vídeo e tente responder às perguntas que você errou.

  4. ASSISTA e LEIA o SCRIPT

    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.

  5. FAÇA as ATIVIDADES

    Existem várias atividades diferentes que se concentram na preparação para o teste, vocabulário, gramática e estrutura de frases.

triangle Vocabulary 어휘 Vocabulário Vocabulario


  • ☐ ☐ ☐ vulnerable [adj] - easy to be infected or hurt by something
  • ☐ ☐ ☐ motivated [adj] - have a strong reason or desire to do something
  • ☐ ☐ ☐ hatch [v] - the opening of an egg to produce babies
  • ☐ ☐ ☐ a proboscis [n] - the long nose of an animal [image] ESL Vocab - A proboscis
  • ☐ ☐ ☐ sophisticated [adj] - not simple
  • ☐ ☐ ☐ a sheath [n] - a long hollow cover that protects something inside
  • ☐ ☐ ☐ saw [v] - cut with a blade that has teeth
  • ☐ ☐ ☐ barely [adv] - almost nothing
  • ☐ ☐ ☐ probe [v] - check, search, test
  • ☐ ☐ ☐ exude [v] - give, discharge
  • ☐ ☐ ☐ a gut [n] - the stomach of an animal
  • ☐ ☐ ☐ free up [phv] - create more space or time by removing something
  • ☐ ☐ ☐ red blood cells [n] - part of the blood
  • ☐ ☐ ☐ stuff [v] - pack, put a lot of something into
  • ☐ ☐ ☐ saliva [n] - water from the mouth
  • ☐ ☐ ☐ There is nothing in it. [exp] - There is no benefit.
  • ☐ ☐ ☐ a parasite [n] - an organism that lives in a host organism and benefits by taking nutrients from the host
  • ☐ ☐ ☐ a parting gift [exp] - a gift that you give when you leave (part)
  • ☐ ☐ ☐ hitching a ride [exp] - getting a ride somewhere for free
  • ☐ ☐ ☐ a welt [n] - a red, swollen mark left on skin after being bitten by a mosquito [image] ESL Vocab - A welt
  • ☐ ☐ ☐ larvae [n] - baby insects
  • ☐ ☐ ☐ rain gutters [n] - shallow troughs at the edge of a roof for carrying off rainwater [image] ESL Vocab - A gutter

[n] - noun,  [v] - verb,  [phv] - phrasal verb,  [adj] - adjective,  [exp] - expression



triangle Questions 문제 Questões Preguntas


  1. The mosquito is the deadliest animal in the world.
    True
    False

  2. Children and pregnant women are mostly immune to mosquito bites.
    True
    False

  3. Only male mosquitoes bite people.
    True
    False

  4. Female mosquitoes need blood to produce eggs.
    True
    False

  5. Mosquitoes need large pools of water to hatch their eggs.
    True
    False

  6. A protective sheath protects the needles inside a mosquito's proboscis.
    True
    False

  7. Mosquitoes have four needles inside their proboscis.
    True
    False

  8. Two of the needles hold the skin apart.
    True
    False

  9. Two of the needles suck up blood from blood vessels.
    True
    False

  10. Mosquitoes need the water in our blood.
    True
    False

  11. Mosquitoes spit a chemical into our skin to make our blood flow more easily.
    True
    False

  12. Mosquito bites are itchy because of this chemical.
    True
    False

  13. This chemical also protects humans from viruses and parasites.
    True
    False



triangle Vocabulary Review 어휘 검토 Revisão de vocabulário Vocabulario revisión


Directions: What expressions from the video have the same meaning as the highlighted expressions in the sentences below?

  1. The most [ at risk ] people: children, pregnant women.

    [ vulnerable ]



  2. They need blood to make eggs and a pool of water for their babies to [ break out of eggs ] in.

    [ hatch ]



  3. But the tools she’s using here are [ complex ].

    [ sophisticated ]



  4. First, a protective [ covering ] retracts.

    [ sheath ]



  5. These other two needles hold the [ skin, organ material ] apart while she works.

    [ tissues ]



  6. From under the skin, you can see her [ testing, searching ], looking for a blood vessel.

    [ probing ]



  7. Receptors on the tip of one of her other needles pick up on chemicals that our blood vessels [ emit, give off ] naturally.

    [ exude ]



  8. As her [ stomach ] fills up, she separates water from the blood and squeezes it out.

    [ gut ]



  9. They get our blood flowing more easily, and give us itchy [ bump, swelling ] afterwards.

    [ welts ]



  10. There’s [ no benefit ] for her.

    [ nothing in it ]



  11. The viruses and parasites are just [ riding for free ].

    [ hitching a ride ]



triangle Sentence Building 문장 만들기 Construção de sentença Construcción de oraciones


Directions: Write sentences about the video clip using the words given. You can change the word form or add words, but you cannot change the word order.
( ) = optional   [ ] = necessary

Instrucciones: Escriba oraciones sobre el videoclip usando las palabras dadas. Puede cambiar la forma de la palabra o agregar palabras, pero no puede cambiar el orden de las palabras.

Instruções:: Escreva orações sobre o videoclipe usando as palavras-chave. Você pode alterar a forma da palavra ou adicionar palavras, mas não pode alterar a ordem das palavras.

지시 : 주어진 단어를 사용하여 비디오 클립에 대한 문장을 씁니다. 어형을 변경하거나 단어를 추가할 수 있지만 어순은 변경할 수 없습니다.



Sentence 1

mosquito / deadly / animal / world


Mosquitoes are the deadliest animal in the world.
The mosquito is the deadliest animal in the world.



Sentence 2

only / female / mosquito / bite / because / they / need / blood / produce / egg


Only female mosquitoes bite because they need blood (in order) to produce (their) eggs.



Sentence 3

they / can / lay / egg / just / tiny / amount / water


They can lay (their) eggs in just a tiny amount of water.
They can lay (their) eggs in just tiny amounts of water.



Sentence 4

a / mosquito / mouth / have / six / needle / each / with / special / function / for / find / and / extract / blood


A mosquito’s mouth has six needles, each with a special function for finding and extracting blood.



Sentence 5

two / needle / saw / through / skin / while / two / other / hold / tissue / apart


Two needles saw through the skin, while two others hold the tissue(s) apart.



Sentence 6

one / needle / suck / blood / like / straw / and / another / inject / saliva / that / help / keep / blood / flow


One needle sucks blood like a straw, and another injects saliva that helps (to) keep (the) blood flowing.



Sentence 7

because / this / saliva / often / carry / virus / parasite / it / can / make / people / sick


Because this saliva often carries viruses [or/and] parasites, it can make people sick.



triangle Discussion 논의 Questões de discussão Discusión


  1. What is the most interesting thing you learned from this video?
  2. What does a mosquito bite look like? How does a mosquito bite feel? Try to describe it in as much detail as possible. You can use some of the vocabulary below:
    (bump, burning sensation, itchy, pinch, sting, swollen, tingling, welt)
  3. How do people usually protect themselves from mosquitoes? Which ways are the most effective? The least effective?
  4. What is the best way to treat a mosquito bite after you have been bitten?
  5. The video says mosquitoes are the deadliest animal in the world. What do they mean by "deadliest" in this context? What are some of the other deadliest animals in the world?
    You can check the list [ here ].
  6. Would you support a scientific project to eliminate mosquitoes completely? Why or why not?

triangle Script 대본 Roteiro Guion


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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