IELTS Preparation Series 1, Episode 7: Enviro-loo
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Hello. I'm
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Margot Politis. Welcome to Study English, IELTS preparation.
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Today we have an environmental theme on Study English, but it's an environmental story with
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a difference.
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We find out about a new toilet system that has been developed to save the local environment
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in a Tasmanian park.
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We're going to be looking at how to talk about processes, so listen carefully to David Holman
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talk about his new environmentally friendly toilet.
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The liquid waste comes from the toilet behind me. There's a containment vessel for the solids.
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From the bottom of the solids you drain off the liquid and it comes down here down this
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pipe.
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OK. The pipe tips into this tipping bucket arrangement and what this does is it fills
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up to a point, and then it suddenly tips and that will measure each time it tips. So we
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can calculate the amount of liquid effluent that's gone in.
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As that fills up, you can see the towelling material here will come in contact with the
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effluent, the air is drawn in through these holes and will actually direct the air in
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onto the surface of the water, through the wick and out through the top.
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OK, so David was talking about how his toilet, the Enviro-Loo, works.
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He was describing a process. Today we're going to look at the type of language you'll need
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to describe processes.
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We'll listen to David again. This time, listen out for the types of verbs he uses.
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The liquid waste comes from the toilet behind me. There's a containment vessel for the solids.
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From the bottom of the solids you drain off the liquid and it comes down here down this
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pipe.
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OK. The pipe tips into this tipping bucket arrangement and what this does is it fills
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up to a point, and then it suddenly tips and that will measure each time it tips. So we
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can calculate the amount of liquid effluent that's gone in.
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David uses a variety of verbs and tenses. But mostly he uses the simple present tense.
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The simple present is often used to describe processes and procedures.
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Let's look at some examples.
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The liquid waste comes from the toilet behind me.
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OK. The pipe tips into this tipping bucket arrangement, and what this does is it fills
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up to a point and then it suddenly tips.
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There's also another, more formal way of describing processes.
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That's using the passive voice.
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In academic writing, it's common to use the passive voice for actions in a process or
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procedure. When you use the passive voice, your writing becomes impersonal and distant.
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This is more formal, and is often more suitable in an academic setting.
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Listen for a passive verb here.
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As that fills up, you can see the towelling material here will come in contact with the
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effluent, the air is drawn in through these holes.
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He says 'is drawn in': the air is drawn in.
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Notice there is no subject, no person or thing doing the action, it is just done. This is
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called the passive voice.
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This highlights the process or action, rather than the person or thing doing the action.
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The passive is used when the important thing is not who did the action, but the action
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itself.
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This is true when you are describing processes. The process is the same, no matter who is
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doing it, so we choose the passive voice.
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Let's look at bit more closely at how the passive is formed.
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Passive verbs are formed by using the verb to be plus the past participle of the verb.
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Let's look at the verb to draw in, to bring something in.
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The past participle is drawn. This is an irregular past participle.
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So the passive form is to be drawn in.
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The different forms of the passive vary according to the action, and when the action happened.
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OK. So in formal writing, we use the passive form for processes. But David doesn't always
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use the passive, because he's having a conversation with someone.
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Let's look at one of David's more informal sentences, and see how we could change it
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into a more formal description.
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There's a containment vessel for the solids and from the bottom of the solids, you drain
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off the liquid.
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He says: From the bottom of the solids you drain off the liquid. Let's look at the main
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part of that sentence:
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You drain off the liquid.
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The verb is drain off.
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In a passive sentence, we'd say 'is drained off', the past participle with the present
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tense form of to be.
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To form the passive, we also need change the sentence around.
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Most English sentences use the active form. That's subject, verb, object. But in the passive,
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sentences begin with the object of the verb: object, verb, subject.
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In this sentence, we know that 'drain off' is the verb, 'you' is the subject and 'the
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liquid' is the object.
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So to form a passive sentence, we'll need to turn the sentence around into object, verb,
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subject. Notice that we add the word 'by'.
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The liquid is drained off by you.
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But in a process, we don't need to include the agent of the verb, so it usually gets
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left out.
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Our new, more formal sentence reads:
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The liquid is drained off.
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So let's go back to that full sentence
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From the bottom of the solids, you drain off the liquid.
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From the bottom of the solids, the liquid is drained off.
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Here's another one:
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We can calculate the amount of liquid that's gone in.
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We can calculate the amount of liquid.
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The subject is 'we'. This will be dropped in our passive sentence.
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The object is 'the amount of liquid'.
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The verb is 'can calculate'.
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'Calculate' has the past participle 'calculated'.
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When there are auxiliary verbs like 'can', we use the infinitive form of the verb 'to
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be'.
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So the full verb phrase 'can calculate' becomes 'can be calculated'.
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Remember that a passive sentence starts with the 'object', then the 'verb', so:
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We can calculate the amount of liquid.
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becomes:
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The amount of liquid can be calculated.
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OK, let's finish today by testing you on the passive.
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Listen to the steps in a simple process.
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This is how you make a cup of coffee. It's in a conversational style.
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You fill the kettle with water. You turn on the kettle.
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You boil the kettle. You pour the hot water into a mug.
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You add some sugar. Then you can drink it.
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OK. Let's start at the beginning.
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You fill the kettle with water.
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What's the verb? Fill. The subject? You. The object? The kettle.
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The passive verb is 'is filled'.
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The new sentence is:
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The kettle is filled with water.
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See if you can do the next one.
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You turn on the kettle.
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The verb is 'turn on'. The subject is 'you'.
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The object is 'the kettle'.
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The kettle is turned on.
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You boil the water. The water is boiled.
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You pour the hot water into a mug. The hot water is poured into a mug.
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You add some sugar. Some sugar is added.
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Then you can drink it. Then it can be drunk.
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But we'd usually say: Then it's ready to be drunk.
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So let's go through that again.
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The kettle is filled with water. The kettle is turned on.
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The water is boiled. The hot water is poured into a mug.
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Some sugar is added. Then it's ready to be drunk.
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And I think I'll go and make a cup of coffee right now.
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Don't forget to practice these active and passive sentences.
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And I'll see you next time for Study English. Bye.