Colour idioms (White)

In this episode the Teacher introduces you to three idiomatic expressions that use the colour white:

1. It's black and white
2. As white as a sheet
3. A white-knuckle ride

View the video at 

http://www.bbc.co.uk/worldservice/learningenglish/language/theteacher/2009/02/090226_teacher_white.shtml

Script

Hello, I’m a very interesting and intelligent man.And today, the colour white and I will be teaching you some English idioms.
I bet you’ve never……Aaah, the world. Such a beautiful place……urgh. How filthy.

The environment is … really important. And if we don’t take care of the environment then…something really bad will happen.For me, it’s black and white.
In English…… if we have situation in which it’s easy for someone to understand what’s wrong and what’s right, we say ‘it’s black and white’.
It’s black and white.

Erm… so it is. It really is black and white.Um, it’s a good thing I don’t really get scared very easily because this place is… not very nice.Argh! What do you mean, I’m as white as a sheet?In English, if someone is very pale because they are ill or shocked or scared, we say they’re as
white as a sheet.
As white as a sheet.

Oh come on, I’m brave! I love roller coasters, for example.Oh, that’s huge!Well, here I go.That was a real white-knuckle ride.In English, if something is very exciting or scary, we call it a white-knuckle ride.
A white-knuckle ride.

Like my lessons. They’re a real white knuckle ride. Oh yeah, so exciting, yeah!… ah, where did everybody go? Where have you all gone?