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.
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Blood clotting will perhaps occur.
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Blood clotting will possibly occur.
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I suspect blood clotting will occur.
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Notice that the adverbials can occur in a number of places in the sentence.
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Blood clotting will perhaps occur.
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Perhaps blood clotting will occur.
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Blood clotting perhaps will occur.
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Blood clotting will occur perhaps.
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Listen to Dr Crantock and the way he structures his argument. Listen for a topic sentence,
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and for the way he lists the different ideas.
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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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The first sentence is the topic sentence. He said: When we're travelling on long haul
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flights, several things happen.
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So we know from this topic sentence, that he is going to tell us about travelling on
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long haul flights.
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But there are lots of things you can say about travelling on long haul flights. So he says
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something else in this sentence that gives us more information. He says several things
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happen.
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This phrase is called the controlling idea. Every topic sentence has a controlling idea.
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It tells us what the focus of the paragraph will be.
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So he's going to be discussing several things that happen on long haul flights.
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In the rest of the paragraph, he lists some of the things that happen. He raises the points
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one by one, and discusses them in detail.
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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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Dr Crantock says first of all, we're stationary.
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This is the first factor in his argument. People are stationary, or sitting still.
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He says: Number two, the environment is dry. This indicates it is the second factor in
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his argument.
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Moving on through the argument, you can keep discussing factors by using transition signals
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such as:
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another factor is
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in addition or additionally
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furthermore
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above all
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You could also use next, but this is quite informal as well.
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The last reason or item in the list could be introduced by lastly or finally.
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It is good practice to watch out for these transition devices when listening to someone
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talk. They'll help you follow an argument more clearly.
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Finally for today, let's look at some definitions. Doctor Crantock gives a definition of the
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condition he is talking about, because it's an unusual medical term.
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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.
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He says: Deep vein thrombosis is where a clot forms in the calf veins.
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This is common pattern for giving a definition.
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First, name the thing being defined. In this case, it's deep vein thrombosis
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Secondly, use the verb to be: is or are.
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Here, we'd say:
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Deep vein thrombosis is
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Thirdly, we can write the class. What kind of thing is it? In this case, DVT is a medical
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condition.
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So we might have:
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Deep vein thrombosis is a condition.
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Next we use a word like which, who, where, or that.
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Deep vein thrombosis is a condition where
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And finally we give the characteristics of the thing. This could be a physical description,
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or a description of behavior. In the case of a medical condition, this would most commonly
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be the symptoms or effects of the condition.
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Deep vein thrombosis is a condition where blood clots form in veins.
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Let's try a couple of examples.
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What is a computer? It stores and processes information.
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A computer, is, a machine, that, stores and processes information.
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What is an accountant? Well we have the phrase analyse and deal with finances.
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An accountant is a person who analyses and deals with finances.
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And what is the time? The time is something that we have run out of for today.
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See you next time on Study English. Bye bye.
