This is News Review from BBC Learning English. I'm Neil.

And I'm Beth.

Stick with us and you can learn the vocabulary to talk about this story.

Yes, you can.

And don't forget to subscribe to our channel, like this video, and try the quiz on our website.

But now, today's story.

Hepatitis. A recent mysterious outbreak of the liver disease has seriously affected over a thousand young children from 35 countries across the world.

Until now, nobody knew why.

But scientists in the UK say the likely cause is two common viruses which came back after the Covid lockdowns ended.

Beth, you've been looking at the headlines. What's the vocabulary?

We have "get to the bottom of", "culprit" and "constellation".

This is News Review from BBC Learning English.

Let's have a look at our first headline.

This one comes from The Sun: Major breakthrough as scientists get to the bottom of mysterious hepatitis outbreak in kids

Now, we're looking at "get to the bottom of" something.

And this is about discovering the truth, isn't it?

Yeah. That's right.

If we get to the bottom of something, we find out the cause of a particular situation.

So in the headline, the mystery illness is the thing that people don't understand, but scientists have been investigating. They're trying to get to the bottom of it.

Now, obviously, disease is a really serious matter. Is this expression only for serious things?

Well, not always serious problems, but certainly negative situations.

So the police would try to get to the bottom of a crime.

Yeah. And now a crime is both negative and serious.

Yeah, but we could also say "someone stole my pen", which is obviously negative, but not so serious. I'm trying to get to the bottom of it.

Yeah. Well, I've seen Beth's pen, and it's really not serious. I can tell you.

But anyway, you might want to get to the bottom of it.

How formal or informal is this expression?

It's informal, so you can use it in conversation, and you wouldn't really see it in official reports.

OK. Well, I'm glad we've got to the bottom of that piece of vocabulary.

Let's have a look, one more time.

Now, let's have our next headline, please.

This one comes from the Mail: Scientists find likely culprit behind mystery child hepatitis outbreak - and Covid itself is NOT to blame

Well, it's a long headline, but we're looking at one word in particular, and it is "culprit".

Are you a fan of crime drama, Beth?

Yeah, I love a good crime drama.

OK, so you will know that the culprit is the person who committed the crime.

Yes. Detectives look for the culprit.

But in this headline, we are not talking about a person that is guilty of a crime, but, actually, the cause of a bad situation.

So, the culprit is not only a person.

That's right.

So, for example, we can say that the wildfires that we've been seeing recently, they have been caused by heatwaves, and scientists say that climate change is the culprit.

Yeah. Now, culprit, crime - it all sounds very formal.

Is it formal? Always?

Well, it is and it isn't.

It kind of depends on the context, like so many of these things.

So, if you saw in an official report of a serious crime, then, of course it's formal.

But, we can also use it for not so serious situations - like more informal.

Yeah. And it's used as a kind of exaggeration to make it kind of funny that saying that something, someone is a culprit when it's just not that serious.

True, true. - Like this pen that I stole.  

Right. Let's look at that again.

Let's have the next headline, then, please.

This one is from The Scientist: Preprints Propose Constellation of Causes for Kids' Liver Disease

According to preprints, preprints are a kind of academic scientific research paper, there are many related causes for this liver disease in children.

In fact, what they call a constellation.

A constellation is a group of stars, though, Beth. So what's the connection?

Yeah. You're right. So a constellation is a group of stars that form a pattern.

For example, everyone knows 'The Plough'. That's the one that looks like a giant spoon.

Yeah. And 'Orion'. That's the one with the stars that make up the belt.

But constellation here is not being used to talk about stars.

It's to say that there is a group of things that are very similar.

And, of course, stars in a constellation look very similar to us, and that's the connection.

Exactly. Yeah.

So in the headline, they are suggesting that there's a group of similar things that are causing this illness.

Now, let's have a look at the pronunciation of this word 'constellation'. Four syllables, but where's the stress?

con-ste-LLA-tion. It's on the third syllable.

Constellation.

OK, let's look at that again.

We've had "get to the bottom of" - find out what happened.

"Culprits'"- who or what is responsible for something bad happening. And it's not just used for crime dramas.

And "constellation" - a group of things that are related.

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Thank you for joining us, and goodbye.

Bye.