IELTS Preparation Series 1, Episode 18: Salinity
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Hello, I’m Margot Politis. Welcome to Study English, IELTS preparation.
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Today we’re going to see an animation about a process called salinity, that’s where
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land becomes damaged by too much salt.
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We’ll be looking at language you can use to describe processes, including transition
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signals. Listen for how the process of salinity is described here.
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One of the main causes of salinity is waterlogging. First, land is cleared for crops to grow.
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Now, instead of trees pumping the water out of the ground, and keeping the salt stored,
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whatever water the crops don’t use percolates down into the soil.
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Gradually, over a number of years, the earth gets wetter and wetter, and eventually it
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waterlogs. Then, the water table starts to rise to the surface. As it rises, it dissolves
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the tonnes of salt stored in the soil.
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Once the water table comes to within two metres of the surface, it begins to evaporate. Lastly,
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the sun extracts the moisture from the ground, leaving the salt concentrated on the surface.
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The first casualties of this dramatic land change, and the dry land salinity that it
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causes, are ecosystems.
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We heard a description of a process. A process has a number of steps from beginning to end.
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When describing a process, the first sentence, or topic sentence, should tell us what the
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main idea of the paragraph is, and what the process is leading to.
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Listen to the topic sentence.
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One of the main causes of salinity is waterlogging.
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One of the main causes of salinity is waterlogging.
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This topic sentence tells us that the paragraph is about salinity, that is, land becoming
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salty.
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And the sentence tells us that one of the main causes of this problem is waterlogging.
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So from this sentence, we expect that the paragraph will be about the process of land
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becoming waterlogged, leading to salinity. When we describe a process, it is important
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that the reader understands when each part of the process happens, what order things
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happen in.
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Listen again to the passage, and watch for the words that order the stages of the process.
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First, land is cleared for crops to grow. Now, instead of trees pumping the water out
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of the ground, and keeping the salt stored, whatever water the crops don’t use percolates
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down into the soil.
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Gradually, over a number of years, the earth gets wetter and wetter, and eventually it
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waterlogs. Then, the water table starts to rise to the surface. As it rises, it dissolves
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the tonnes of salt stored in the soil.
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Once the water table comes to within two metres of the surface, it begins to evaporate.
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Lastly, the sun extracts the moisture from the ground, leaving the salt concentrated
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on the surface.
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She uses a range of transition signals to order the stages of the process.
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One type of transition signal is ordinal numbers. Listen.
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One of the main causes of salinity is waterlogging. First, land is cleared for crops to grow.
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The ordinal numbers are first, second, third, fourth and so on.
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These ordinal numbers can be used as adjectives to form phrases describing order.
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We can either just start the sentence with:
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First,
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Second,
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or we can use them in phrases like these:
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The first step is
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The second stage begins when
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The third part is.
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We can also add 'ly’ to ordinal numbers to make adverbs:
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firstly, secondly, thirdly, fourthly, etc.
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Using these words is a very common and simple way of ordering stages in a process.
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You can also use them to organise any group of ideas, examples or points in an argument.
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Another type of transition signal is time phrases she uses is time phrases.
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Gradually, over a number of years, the earth gets wetter and wetter,
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Gradually, over a number of years, the earth gets wetter and wetter.
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The phrase, "Gradually, over a number of years," tells us that this part of the process takes
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place gradually, slowly, over a number of years, over many years.
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It is a long, slow process.
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Over a number of years is a time phrase. Using time phrases helps to make the descriptions
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of processes clearer.
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Other useful time phrases you might come across are:
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at this stage
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during this process
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after several days
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All of these phrases tell us when, or for how long, that stage in the process takes
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place.
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Listen again:
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Then the water table starts to rise to the surface. As it rises, it dissolves the tonnes
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of salt stored in the soil.
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She says as it rises.
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The word as tells us that two actions are taking place together, or simultaneously.
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While the water table is rising to the surface, it dissolves the salt.
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Other phrases indicating two actions taking place at the same time could be at the same
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time, meanwhile.
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There are some other adverbs you can use as transition signals. Which ones were used in
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the passage?
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Listen:
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Now, instead of trees pumping the water out of the ground, and keeping the salt stored,
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whatever water the crops don’t use percolates down into the soil.
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Gradually, over a number of years, the earth gets wetter and wetter, and eventually it
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waterlogs. Then, the water table starts to rise to the surface. As it rises, it dissolves
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the tonnes of salt stored in the soil.
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She uses the adverbs now, eventually, then and lastly.
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These all help to order events.
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There are many other adverbs to choose from. Make sure you use a wide variety of them in
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your writing and speaking, rather than just repeating the same ones.
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Others include: finally, subsequently, later, afterwards.
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OK. We’re going to finish today by looking at some pronunciation.
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There are a number of English words that can be used as both nouns and verbs.
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However, in many cases, the pronunciation of these changes. This can be quite difficult
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to get used to.
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Listen to the word extracts in the passage:
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Lastly, the sun extracts the moisture from the ground, leaving the salt concentrated
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on the surface.
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The sun extracts the moisture.
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Extracts here comes from the verb to extract.
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Where is the emphasis, or stress in this word?
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It’s on the second syllable exTRACT.
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But extract is also a noun.
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When it’s a noun, it’s pronounced EXtract. The emphasis is now on the first syllable.
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And this pattern of first syllable emphasis for the noun form, and second syllable emphasis
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for the verb form, is repeated with other words.
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We have:
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to exTRACT and an EXtract
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to conTRACT and a CONtract
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to consTRUCT and a CONStruct
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and there are lots of others.
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We have PROduce, that you eat and to proDUCE, to make
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We have SUBject and Object but subJECT and obJECT
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Let’s test you. Try reading these sentences:
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He objected to the subject of the lesson.
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The farm produced fresh produce.
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So you can see how the stress in words can change meaning. You’ll have to practice
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whenever you can!
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And after all that, it must be time to go. See you next time on Study English.
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Bye bye.
