Pratique du Shadowing: What’s in the air you breathe? - Amy Hrdina and Jesse Kroll - Apprendre l'anglais à l'oral avec YouTube

C2
Take a deep breath.
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40 phrases
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Take a deep breath.
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In that single intake of air, your lungs swelled with roughly 25 sextillion molecules, ranging from compounds produced days ago, to those formed billions of years in the past.
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In fact, many of the molecules you’re breathing were likely exhaled by members of ancient civilizations and innumerable humans since.
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But what exactly are we all breathing?
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Roughly 78% of Earth’s atmosphere is composed of nitrogen generated by volcanic activity deep beneath the planet’s crust.
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The next major ingredient is oxygen, accounting for 21% of Earth’s air.
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While oxygen molecules have been around as long as Earth’s oceans, oxygen gas didn’t appear until ocean dwelling microorganisms evolved to produce it.
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Finally, .93% of our air is argon, a molecule formed from the radioactive decay of potassium in Earth’s atmosphere, crust, and core.
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Together, all these dry gases make up 99.93% of each breath you take.
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Depending on when and where you are, the air may also contain some water vapor.
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But even more variable is that remaining .07%, which contains a world of possibilities.
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This small slice of air is composed of numerous small particles including pollen, fungal spores, and liquid droplets, alongside trace gases like methane and carbon dioxide.
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The specific cocktail of natural and man-made compounds changes dramatically from place to place.
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But no matter where you are, .07% of every breath you take likely contains man-made pollutants— potentially including toxic compounds that can cause lung disease, cancer, and even DNA damage.
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There’s a wide variety of known pollutants but they all fall into two categories.
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The first are primary pollutants.
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These toxic compounds are directly emitted from a man-made or naturally occurring source.
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However, they don't always come from the places you'd expect.
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Some large factories mostly generate water vapor, with only small quantities of pollutants mixed in.
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Conversely, burning wood or dung can create polycyclic aromatic hydrocarbons; dangerous compounds that have been linked to several types of cancer, as well as long-term DNA damage.
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In all cases, pollutants interact with regional weather patterns and topography, which can keep compounds local or spread them kilometers away.
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When these molecules travel through the air, a transformation occurs.
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Natural compounds called oxidants, formed by oxygen and sunlight, break down the pollutants.
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Sometimes, these reactions make pollutants more easily washed out by rain.
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But in other cases, they result in even more toxic secondary pollutants.
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For example, when factories burn coal, they release high concentrations of sulfur oxides.
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These molecules oxidize to form sulfates, which condense with water vapor in the air to form a blanket of fine particles that impair visibility and cause severe lung damage.
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This so-called sulfurous smog was well-known in 20th century London and continues to plague cities like Beijing.
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Since the advent of cars, another secondary pollutant has taken center stage.
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Exhaust from fossil fuel-burning vehicles releases nitrogen oxides and hydrocarbons which react to form ozone.
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And while some ozone in the upper atmosphere helps shield us from ultraviolet rays, on the ground, this gas can form alongside secondary particles and create photochemical smog.
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This brown fog can be found covering densely packed cities, making seeing difficult and breathing hazardous.
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It also contributes to climate change by trapping heat in the atmosphere.
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In recent decades, industrial activity has contributed to a huge spike in various trace gas emissions, fundamentally changing the air we all breathe.
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Many places have already responded with countermeasures.
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Most cars produced since the 1980′s are equipped with catalytic converters that reduce the emission of carbon monoxide and nitrogen oxides.
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And today, places like Beijing are battling smog by electrifying their energy infrastructure and limiting automobile emissions altogether.
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But while moving away from fossil fuels is essential, there's no universal remedy for air pollution.
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Different regions need to respond with unique regulations that account for their local pollutants.
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Because no matter where you live, we all share the same air.

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About This Lesson

In this lesson, learners will explore the fascinating components of the air we breathe, as presented in the video "What’s in the air you breathe?" by Amy Hrdina and Jesse Kroll. Through listening and speaking practice, you will enhance your vocabulary related to environmental science and air quality, while also employing the shadowing technique to improve fluency and pronunciation. You will engage with complex topics such as air composition, pollutants, and their implications on health, making this a rich resource for those preparing for IELTS speaking practice or simply seeking to elevate their English-speaking skills.

Key Vocabulary & Phrases

  • Molecules - The smallest units of a chemical compound; essential for understanding air composition.
  • Pollutants - Substances that contaminate the air, affecting health and the environment.
  • Primary Pollutants - Toxic compounds emitted directly from sources like factories or vehicles.
  • Secondary Pollutants - Harmful compounds formed when pollutants react with other substances in the air.
  • Oxidants - Natural compounds that help break down pollutants when combined with sunlight and oxygen.
  • Photochemical Smog - Brown fog formed from vehicle emissions and sunlight, hazardous to breathe.
  • Catalytic Converters - Devices used in vehicles to reduce harmful emissions.
  • Air Quality - The measure of pollutants in the air and its impact on health.

Practice Tips

To maximize your learning experience using the shadowing technique, start by watching the video with subtitles. Repeat the phrases after the speakers, mimicking their tone and pace. The video features a moderate speed that is ideal for beginners to intermediate speakers. Focus on the intonation and rhythm of the sentences as you practice your shadow speech. Try to pause the video at key points to understand complex phrases before resuming.

As you engage with this lesson, integrate IELTS speaking practice by selecting vocabulary from the lesson and crafting your own sentences. Discuss how pollutants impact the environment using the newly learned terms, enhancing both your speaking skills and contextual understanding. Remember to record yourself and listen for improvements—this will help refine your technique as you fine-tune your pronunciation and fluency.

Qu'est-ce que la technique du Shadowing ?

Le Shadowing est une technique d'apprentissage des langues fondée sur la science, développée à l'origine pour la formation des interprètes professionnels. Le principe est simple mais puissant : vous écoutez de l'anglais natif et le répétez immédiatement à voix haute — comme une ombre suivant le locuteur avec un décalage de 1 à 2 secondes. Les recherches montrent une amélioration significative de la précision de la prononciation, de l'intonation, du rythme, des liaisons, de la compréhension orale et de la fluidité.

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