Today we're going to look at intonation- how we use a rising or falling tone of voice to

convey meaning - and we'll also have a quick look at how to use commas.

But first, let's watch a clip about sleep. We'll see a researcher doing some tests on

a subject, to see just what the benefits are of an afternoon nap.

Researchers at Flinders University say a short sleep in the mid afternoon could actually

increase a worker's productivity.

Each subject performed a series of tests before and after their mid afternoon sleep.

Some subjective tests of alertness, fatigue, vigour, and also some cognitive performance

tasks, some which are pencil and paper and some that are done on the computer, and also

an objective measure of alertness, which is how long it takes someone to fall asleep.

So if it takes them a long time to fall asleep, that would suggest that they're quite alert,

and a short time to fall asleep would mean that they're quite sleepy.

Do you think you were asleep?

Yes, hard to tell but I think so. I think I did for a bit.

For how long?

It felt like probably a couple of minutes, I reckon.

I want you to do exactly the same thing now. I want you to start here and want you to go

as quickly and as accurately as you can until I tell you to stop.

So in that clip we heard a researcher talking to the subject of her tests.

You'll notice her intonation changed a lot.

Intonation refers to the changes in pitch in our voice as we speak - whether our voices

go up, or down.

Intonation is very important to learn. It has many functions in a language.

It conveys emotion. We can tell immediately listening to someone how they feel.

Someone can sound happy, or sound sad.

Hello, how are you?

Hello, how are you?

Intonation also conveys meaning. It let's the listener know whether something is a question

or a statement, or it can indicate different levels of certainty or uncertainty.

Hello, are you well?

Hello, are you well?

Learning intonation is especially helpful for learning to ask questions, and indicating

what sort of answer we expect.

Watch part of the clip again, and listen closely to the intonation as the doctor talks to her

subject.

Do you think you were asleep?

Yes, hard to tell but I think so. I think I did for a bit.

For how long?

It felt like a couple of minutes, I reckon.

The doctor says to the subject, "Do you think you were asleep?"

Does this have a rising or falling tone?

Listen again.

Do you think you were asleep?

Do you think you were asleep?

Her voice goes up at the end of the sentence. We call this a rising tone.

The rising tone is used for yes/no questions - questions that need a yes or no answer.

Listen now to the second question. Does it have a rising or falling tone?

For how long?

It felt like a couple of minutes, I reckon.

The doctor says, "For how long?"

This is a question too, but it has a falling tone.

A falling tone is used with information questions.

They're questions that need information as an answer, not just a yes or no answer.

The man answers with a statement: A couple of minutes, I reckon. This takes a falling

tone.

In English, statements usually end in a falling tone.

The falling tone at the end tells the listener that the statement is finished.

Listen to the intonation used to give instructions.

I want you to start here and I want you to go as quickly and as accurately as you can

until I tell you to stop.

Did you hear the falling tone at the end?

She said, "until I tell you to stop".

This tells the listener that this is the end of the instruction.

So, let's look at when to use rising and falling tones again.

A rising tone is used at the end of yes/no questions, and a falling tone at the end of

information questions.

Falling intonation is also used with statements.

These are very general rules, but they can help you to work out what you, as a listener,

are expected to say, and can help you, as a speaker, to convey your meaning.

Now, let's look at one last example of intonation.

Listen to what happens when we have a list in a sentence. Here's a very complicated list.

Some subjective tests of alertness, fatigue, vigour, and also some cognitive performance

tasks, some which are pencil and paper and some that are done on the computer, and also

an objective measure of alertness, which is how long it takes someone to fall asleep.

So she uses a variety of intonation. She uses rising and falling tones, and a tone that's

neither rising nor falling - just a flat tone, for the items in the list.

This tells the listener that she hasn't finished her list of tests.

And then, for the very last item in the list, how long it takes someone to fall asleep,

she uses falling intonation. This is how we know the list is finished.

We use generally use falling intonation for the last item in a list.

So you can see there are some rules for intonation, but of course it varies according to the situation,

and our attitudes to the topic.

OK, so when we're talking, we use intonation, pauses and body language to convey meaning.

But what about when we're writing?

Well, we need to use punctuation.

Let's look at one of the most common but difficult punctuation items - the comma.

Commas are used to help readers understand the exact meaning of a sentence. They're like

pauses in speech.

A comma in the wrong place can give the wrong meaning to a sentence.

For example, look at these two sentences:

Stop, Jane!

Stop Jane.

In the first sentence, the comma shows where there is a pause in speech, "Stop, Jane",

and this tells us that the speaker wants Jane to stop.

In the second sentence, there is no pause and no comma - "Stop Jane."

With no pause, we know that the speaker is telling someone else to stop Jane.

Let's look at some rules about using the comma.

First, commas are used to separate items in a list.

Look at the way commas are used here

Some subjective tests of alertness, fatigue, vigour,

and also some cognitive performance tasks.

OK, so notice that when we write down her speech, we put commas where she uses pauses

and we use intonation to separate the items in a list.

We write alertness, fatigue, vigour. We read this as alertness fatigue vigour.

Adding a comma between items in a list tells us clearly how many different items there

are.

A second use of commas is to separate clauses in a sentence.

We use a comma to separate dependent and independent clauses, but only when the dependent clause

is first in the sentence.

This sounds complicated, but it's not really. Here's an example of a dependent clause:

because he was very tired

followed by an independent clause:

he went to bed.

Notice that we use a comma.

Because he was very tired, he went to bed.

But let's swap the clauses around:

He went to bed because he was very tired.

In sentences like this, with the independent clauses first, we don't need a comma.

Listen to the different way they're read out, and you can hear why:

Because he was very tired, he went to bed. Notice the pause.

He went to bed because he was very tired. There's no pause.

So sometimes when you're writing, it helps to think that if there's a pause, you might

need a comma.

And that's where we're going to pause today. Hope you enjoyed Study English, I'll see you

next time. Bye bye.