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Hello, this is 6 Minute English from BBC Learning English. I'm Sam.

And I'm Neil.

Your friend Alicia phoned and left a message for you, Neil. She's sorry, but she has to cancel lunch today.

I think she's going with Jenny instead.

That's the third time this week they've had lunch together. They're best friends now.

Sounds like Neil has a case of the green-eyed monster. In other words, jealousy.

The fear that someone else may take something you think is yours.

Humans have struggled with jealousy for thousands of years.

Jealousy damages friendships, destroys relationships, and can even become a motive for murder.

In this programme, we'll discuss jealousy to find out what happens when the green-eyed monster raises its ugly head.

And as usual, we'll be learning some useful new vocabulary.

Meanwhile, my friend Alicia will be having lunch with Jenny instead of me.

Oh, feeling jealous is no fun. Maybe this question will take your mind off it.

The expression the green-eyed monster comes from a speech in one of William Shakespeare's most famous plays.

But which one? Is it a Romeo and Juliet?

B. Hamlet or C. Or fellow?

I think the answer is a fellow.

OK, Neil. I'll reveal the answer later in the programme.

For many people, feelings of jealousy occur in romantic relationships.

Here, psychologist, Dr. Alex Milky, explains why to the BBC World Service programme, Crowdscience.

So you have a friend, a significant other, your parents, and you have the feeling that this relationship is threatened by someone else,

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