Podcast 40 - B1 Use of the passive - introduction

The structure of the passive

Hello, and today I'm going to talk to you about the passive, I think the first thing we can do is look at the structure of the passive and compare it with the active. Now, let's take a simple sentence,

The men built a bridge.

A bridge was built

That sentence we say is in the active because at the beginning of the sentence, we have the subject or rather, the people who actually did the action, followed by the verb, and then the direct object. Now, the structure of the passive is when we put the direct object in front of the sentence. So we start the sentence with,

A bridge...

The next step is to put the verb to be (and there's always a verb to be in a passive sentence) to put the verb to be in the same tense and aspect as the active form. So, if in the active it was the men built a bridge, built is past simple, so we'll put the verb to be in the past simple.

A bridge was...

Now, the final step is to put the main verb from the active into the past participle. So, the past participle of build is also built. So the final sentence will be

A bridge was built.

Now, it is possible to add what we call the agent. The agent is the old subject from the active form. We put it at the end of the passive - usually introduced by the preposition by. So finally, we have then

A bridge was built by the men.

Okay, so that's the structure. And if we are using other tenses and other aspects, or modal verbs, the procedure is exactly the same. So for example, if we say in the active form,

They can't do it.

So that's using the modal can in the negative, and it's in the present. So we'll put the passive as,

It can't be done.

Because the verb after can must be an infinitive, so they can't do it. We'll put that verb also in the infinitive in the passive, but convert it to the verb to be, so, it can't be done.

We could have more complex tenses, for example, continuous tenses.

They were watching the criminal,

So the passive would be,

The criminal was being watched,

because they were watching is past continuous and so in the passive we will put the past continuous of the verb to be.

Now, I think another thing is that all that's fine, isn't it? And there are a lot of little exercises where you are instructed (are instructed - that's a passive, isn't it?) where you are instructed to change the active form into the passive, or change the passive into the active. And that's all very nice and very well, and it gets you a few marks in your test. But it's important to realise and to understand why we use the passive.

Why we use the passive

Now, there is more than one reason. One reason would be we use the passive instead of the active because, well, it's fairly obvious who does the action.

That one I just said there about,

They were watching the criminal.

Let's say it is the police who are watching the criminal, the police were watching the criminal. So if we put that into the passive, and it seems reasonable, it would be,

The criminal was being watched.

Now, are we going to say, by the police, well, perhaps it's not necessary, because we assume that in most cases, that criminals are tracked and pursued by the police. So perhaps it's just enough to say the criminal was being watched. And then perhaps later,

The criminal was arrested,

without adding the agent, without saying by the police. So that's one reason.

Another reason might be that we just don't know who carried out the action - who did the thing. And perhaps what we want to concentrate on is not who did it, but that it was done. In other words, we want to concentrate on the verb, and not so much on the subject. Now, let's say for example, you're at the airport, and you have your suitcase with you. And well, you were sitting there and looking the other way. And then when you look around, you notice that your suitcase has gone. Oh, my goodness, it's gone. So you go up to the security guard, and you say,

Excuse me, my suitcase has been stolen.

You don't know who stole the suitcase, and it's not really important at this moment. The fact is, what you want to tell the security guard is that it has been stolen.

And then there's a third reason, and this is probably just due to the importance that we put on the subject or on the object. Now, let us say that we're talking about inventors. Now it's usual in English to put the important information at the front of the sentence. So let's say we're talking about three inventors: Marconi, John Baird, and Alexander Graham Bell. So we're talking about inventors. And we say,

Marconi invented the radio.
John Baird invented the television.
Alexander Graham Bell invented the telephone.

So all those are in the active and it sounds natural to say it that way. But what about if we were talking about the inventions and not the inventors? So we'll start with the radio. Yes.

The radio was invented by Marconi.

And then there was another invention wasn't there? Ah, yes, the television.

The television was invented by John Baird.

And then another invention. Another important one, the telephone. Yes.

The telephone was invented by Alexander Graham Bell.

So really that explains why we use the passive - just because we're talking about the object of the sentence, which are the inventions.

That's all from me for today. Goodbye.

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