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.

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