IELTS Preparation Series 1, Episode 16: DVT
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Hello, and welcome again to Study English, IELTS Preparation. I'm Margot Politis.
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If you've been on a flight recently, you will have heard about the danger of sitting still
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for a long time in an aeroplane, apart from the danger of boredom that is!
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The danger is from a condition called deep vein thrombosis, or DVT.
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Today on Study English we'll listen to a doctor talk about DVT, then we're going to look at
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how to talk about things that might happen in the future.
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Deep vein thrombosis is where a clot forms in the calf veins and occasionally in the
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veins of the leg, sometimes in the veins of the pelvis, and this is a great concern because
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the clot may dislodge, travelling with the flow of blood into the right side of the heart
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and from there into the lung.
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When we're travelling on long haul flights, several things happen. First of all, we're
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stationery. We're not moving our legs, so there's no physiological compression of the
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calf muscles. Blood tends to sit in the veins and may clot.
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Number two, the environment is dry. We dehydrate, we may drink some alcohol. We dehydrate even
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further. Alcohol's a diuretic agent, and it results in us actually drying out, and that
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makes the blood a little bit thicker and stickier, and these factors lead to clotting.
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Sometimes, in perhaps particularly the economy section of an aeroplane, we may be a little
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bit cramped and our leg may be slightly compressed on the seat. This could further prevent blood
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flow back to the heart and trap blood in the leg, where clotting may occur.
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Dr Crantock was talking about things that that could happen, may happen, or perhaps
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will happen in the future.
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Perhaps is an adverb. It is a word like maybe or possibly. It gives a statement the sense
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that the speaker is not sure if the thing will happen.
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Perhaps I will means the same as possibly I will, or maybe I will.
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May and could are modal verbs.
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May has a number of meanings. The most common use is when you are asking permission.
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May I come in? Yes you may.
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But the other use of may is to talk about possibilities in the future.
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I may come in tomorrow means in the future, I will possibly come in, but it's not definite.
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Could has a number of meanings too.
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The first is ability.
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"When I was little I could swim," means when I was young, I was able to swim.
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But could is also used to express future possibilities.
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It could rain tomorrow. It's not definite, but it might rain.
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Dr Crantok is talking about what can happen sometimes on flights, but it won't definitely
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happen. Listen again:
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Sometimes, in perhaps particularly the economy section of the aeroplane, we may be a little
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bit cramped and our leg may be slightly compressed on the seat. This could further prevent blood
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flow back to the heart and trap blood in the leg, where clotting could occur.
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So for speculating, or thinking about what will happen in the future, we can use adverbials
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like possibly or perhaps:
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we can use modal verbs like may and could
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and we can use phrases like I guess, I imagine, I suspect.
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So in the clip he says blood clotting could occur.
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We can also say:
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Blood clotting may occur.