IELTS Preparation Series 1, Episode 2: Vitamin D
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Hello. I'm Margot Politis. Welcome to Study English, IELTS preparation.
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Today, we're going to look at ways of discussing a topic. When you're writing or speaking,
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you can present facts, or you can use your opinion - but how can you tell the difference?
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Today we'll find out.
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We're going to listen to a scientist talking about Vitamin D and cancer.
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In the clip, see if you can hear both facts and opinions being used.
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I believe that the public health problem for vitamin D deficiency is quite significant.
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I would estimate minimum 25% of adults in the United States, Europe and probably even
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in Australia are vitamin D deficient.
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I mean if you think about it, over 250,000 women in the United States will develop breast
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cancer this year. Something like 50,000 will die. If 25% of those breast cancers could
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have been averted, prevented in some way, just by having a little exposure to sunlight,
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would have been really tremendous.
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So he was talking about the links between vitamin D and cancer.
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Many Australians these days are avoiding the sun, because they know it can cause skin cancer.
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But by avoiding the sun, they're missing out on vitamin D - the vitamin that you get from
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sunshine, and this is leading to other health problems.
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When you're reading, writing or listening to an argument like this, it's important to
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be able to tell the difference between statements of fact, and statements of opinion.
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But how can you tell the difference?
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Well, there are a number of ways you can express your opinion.
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Today we're going to look at two of these: using phrases that express an opinion; and
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using modal verbs.
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First, let's look at some phrases.
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The key words to listen for when you're trying to decide whether someone is talking about
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facts or opinions are words like believe, think, argue, feel, opinion, or view.
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These vary from formal to informal.
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If I was talking with my friends, I might say, "I think" or "I believe"
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If I was in a class or tutorial, I might say, "In my opinion", or "in my view".
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But if I was writing an essay, or giving a very formal talk, I'd probably choose, "it
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is believed", or "it is thought".
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In formal writing, many people think you should avoid using the word 'I', even if you are
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giving an opinion.
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Here's the clip again. Listen for some of those phrases.
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I believe that the public health problem for vitamin D deficiency is quite significant.
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I mean if you think about it, over 250,000 women in the United States will develop breast
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cancer this year. Something like 50,000 will die.
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Another way we can express opinions is by using modal verbs.
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Model verbs express opinions and attitudes. They make statements less certain or less
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definite.
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They can also be used for recommending and advising.
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Here are the modal verbs used for opinions: would
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should could
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might
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These words signal that the speaker is giving an opinion.
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Look at these examples. Can you tell which ones are facts, and which ones are opinions?
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Fifty thousand will die. Fifty thousand might die.
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The second statement uses might - it is an opinion.
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Here's another one:
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I do not think small amounts of sunlight increase the risk of cancer.
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Small amounts of sunlight do not increase the risk of cancer.
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In the first statement, you can see 'I do not think'. This is an opinion.
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Now look at these 2 sentences:
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I believe that vitamin D deficiency might become common among adults.
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Vitamin D deficiency will affect 25% of adults.
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The first is an opinion - 'I believe', 'might become'.
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The second is a fact - 'will affect' 25% of adults.
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Now let's watch the clip again - listen for the phrases and modal verbs of opinions.
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I believe that the public health problem for vitamin D deficiency is quite significant.
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I would estimate minimum 25% of adults in the United States, Europe and probably even
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in Australia are vitamin D deficient.
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I mean if you think about it, over 250,000 women in the United States will develop breast
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cancer this year. Something like 50,000 will die. If 25% of those breast cancers could
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have been averted, prevented in some way, just by having a little exposure to sunlight,
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would have been really tremendous.
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OK, so you can see that Professor Holick is expressing an opinion, using a combination
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of phrases and modal verbs.
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But now we're going to look at some pronunciation tips.
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When you're learning English, there are 3 very important parts of pronunciation. They
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are: word stress, sentence rhythm and intonation.
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Today we're going to look at the first 2 - how you can practice word stress and sentence
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rhythm together, to improve your spoken English.
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Listen to this sentence closely for word and sentence stress.
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I don't think we should blame moderate, intelligent exposure to sunlight throughout our lives
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as the culprit for markedly increasing our risk of developing skin cancer.
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Notice that the speaker uses many words with more than one syllable. That is common in
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formal academic language.
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But when you come across longer words, you have to learn which syllable to stress.
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For example, we say: intelligent, increasing, and markedly.
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Notice that when you stress one syllable, the vowels in the other syllables are shortened.
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Sometimes these short syllables become a schwa - an 'uh' sound - or an 'i'. They're short,
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relaxed sounds.
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Listen to: moderate
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intelligent exposure
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culprit markedly
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developing cancer
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This shortening of syllables preserves the overall sentence rhythm. Listen to the clip
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again.
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I don't think we should blame moderate, intelligent exposure to sunlight throughout our lives
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as the culprit for markedly increasing our risk of developing skin cancer.
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So when you're learning to speak English, you need to learn the pronunication of individual
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words. But you also need to practice sentence rhythm - putting the words together into sentences.
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This is much easier when you get used to shortening the non-stressed vowels.
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OK. Listen again to the clip, and then we'll practice some more:
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I mean if you think about it, over 250,000 women in the United States will develop breast
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cancer this year. Something like 50,000 will die.
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If 25% of those breast cancers could have been averted, prevented in some way, just
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by having a little exposure to sunlight, would have been really tremendous.
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OK, now you can try it. Listen to this sentence:
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It would have been tremendous to have averted or prevented significant vitamin D deficiency.
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Let's look at each of those words - we'll highlight which syllable is stressed. See
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if you can work out how to pronounce each word.
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tremendous averted
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prevented significant
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vitamin deficiency
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Now let's see what happens when we put these words back into a sentence.
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It would have been tremendous to have averted or prevented significant vitamin D deficiency.
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Making your spoken English sound natural takes a lot of practice.
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Don't forget to listen closely to vowel sounds and sentence stress, and remember to practice
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reading and writing in English every day.
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And that's all from me today.
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I'll see you next time on Study English. Bye.
