IELTS Preparation Series 1, Episode 12: Carbon Cycle

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Hello, I'm Margot Politis. Welcome again to Study English, IELTS preparation.

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Today, we're going to look at cycles, at phrasal verbs, and then we'll finish with a bit of

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punctuation.

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But now, here's a man who is a microbiologist and a mushroom grower.

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He's talking about mushrooms, and the part they play in the carbon cycle.

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They occur naturally in the forests as wood degrading fungi. That's their job. When trees

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die, they grow on the tree. They break down the lignin and the cellulose, which is the

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most resistant form of carbon, and they break it down, produce mushrooms and, in turn, you

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end up with organic matter going back into the soil, and so the carbon cycle in the forest

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goes on.

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The speaker, Noel Arrold, is talking about how mushrooms grow naturally.

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They are an important part of the carbon cycle, but what is a cycle?

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A cycle is a process that is repeated over and over. It goes around and around.

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But how do we know this from listening to Noel?

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When trees die, they grow on the tree. They break down the lignin and the cellulose, which

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is the most resistant form of carbon, and they break it down, produce mushrooms and,

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in turn, you end up with organic matter going back into the soil, and so the carbon cycle

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in the forest goes on.

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He says: and so the carbon cycle in the forest goes

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on.

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By saying the cycle goes on he is telling us that this process happens again and again.

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At the end of the description, you need to signal that the process goes back to the beginning

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again.

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We can say:

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The process goes on.

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The process begins again.

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The process repeats itself.

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In a cycle, there is no real end or beginning, because the process just keeps going.

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When describing a cycle, we need to start somewhere, then describe, in order, each part

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of the cycle.

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There are many different ways of describing the stages of a cycle. We can use transitional

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signals like when, once, then, or next. When speaking, you can also use pauses and intonation

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to describe a cycle. In written language, this becomes punctuation.

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Listen to Noel Arrold again describing the different parts of the cycle.

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When trees die, they grow on the tree.

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He says:

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When trees die, they grow on the tree.

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When trees die comma, they grow on the tree.

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The first part of the cycle is that the trees die.

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The second part is that when the trees die, fungi grow on the trees.

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That's the next stage.

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When trees die, they grow on the tree.

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They break down the lignin and the cellulose, which is the most resistant form of carbon,

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and they break it down, produce mushrooms.

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OK, he says that the fungi break down the lignin and the cellulose. They break down

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the tree.

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So the third stage is that the fungi break down the tree.

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Fourth, they produce mushrooms.

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When trees die, they grow on the tree.

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They break down the lignin and the cellulose, which is the most resistant form of carbon,

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and they break it down, produce mushrooms and, in turn, you end up with organic matter

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going back into the soil.

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He says in turn organic matter goes back into the soil.

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In turn signals the next stage of the process. In turn means next, or because of that.

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That's the fifth stage. The organic matter goes back into the soil.

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And then what happens?

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When trees die, they grow on the tree.

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They break down the lignin and the cellulose, which is the most resistant form of carbon,

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and they break it down, produce mushrooms and, in turn, you end up with organic matter

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going back into the soil, and so the carbon cycle in the forest goes on.

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The carbon cycle in the forest goes on.

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The organic matter helps new trees to grow again, and then those trees die. We're back

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to the first stage again. This is the carbon cycle.

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OK, now we're going to look at some phrasal verbs.

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Phrasal verbs consist of a verb followed by a preposition. This forms a new verb, one

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sometimes related to the original verb, but sometimes not.

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Phrasal verbs are idiomatic. There's no pattern to the meanings they take, and they often

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have a number of different meanings.

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You often can't just guess the meanings of phrasal verbs, you have to learn them.

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Let's look at the phrasal verbs in this clip.

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They break down the lignin and the cellulose which is the most resistant form of carbon,

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and they break it down, produce mushrooms and, in turn you, end up with organic matter

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going back into the soil, and so the carbon cycle in the forest goes on.

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There were four phrasal verbs.

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They were:

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break down end up

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and two using go - go back and go on.

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Notice that sometimes the preposition will give you an indication as to what the phrasal

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verb might mean.

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Let's look at these four.

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See if you can match the meanings.

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break up end up

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go on go back

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and finish continue

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decompose return

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Well break up means to decompose, go back means to return, go on means to continue,

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and end up means to finish.

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But notice that break up can sometimes mean finish as well - we can break up from school.

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In formal writing, we would be more likely to use words like continue or return, than

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phrasal verbs, which tend to be less formal. Phrasal verbs are difficult to learn because

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there are so many of them.

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Look at go. We've already seen it with go back and go on, but there's many, many more,

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and remember, most of these have more than one meaning.

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It takes a lot of time to get used to all the phrasal verbs and what they mean. You

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need to listen carefully to people speaking, and the way they use phrasal verbs.

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Another important thing to do is to write them down in groups - and buy a good phrasal

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verb dictionary.

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So pay attention to those phrasal verbs. Learning them in groups can be fun, and your spoken

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English will sound much more natural.

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Now we're going to look at some writing tips.

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For variety, it's important that you use a lot of different of sentence types, of different

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lengths. The difficult thing is finding the balance.

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You can join together short sentence using conjunctions, but what do you do with sentences

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that are too long?

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This sentence has many ideas, all joined together with 'and'.

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How many 'ands' are there in the sentence?

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They break down the lignin and the cellulose, which is the most resistant form of carbon,

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and they break it down, produce mushrooms and, in turn, you end up with organic matter

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going back into the soil, and so the carbon cycle in the forest goes on.

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There are four 'ands'. This sentence is too long, and should be edited. The ideas can

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be broken down into smaller groups and shorter, clearer sentences.

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There are several ways of doing this. We can use punctuation, conjunctions and connectors.

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So let's have a look. Here's the full sentence.

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We can start by using punctuation.

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Use a comma to separate clauses.

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Use full stops to separate complete ideas and you can replace some of the 'ands' with

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full stops, but remember the new sentence must now start with a capital letter.

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Now we have a clear paragraph, expressing a number of ideas with different kinds of

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sentences.

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And the carbon cycle goes on, but we can't go on - it's time to end this episode of Study

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English, but I'll see you next time. Bye bye.

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