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
3:04
waterlogs. Then, the water table starts to rise to the surface. As it rises, it dissolves
3:12
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