The London Olympic Games are coming soon. This summer, Chinese sports fans will be able to watch the exciting games in 3-D on CCTV.
When you watch 3-D movies or TV, you have to wear a special pair of glasses. The 3-D glasses make the people and the things on the screen look like they are in the room with you.
3-D, means having three *dimensions: *width, height and *depth. 3-D technology is based on the way the human brain and eye work. Because the *pupils of a person’s eyes are about 6.5cm apart, when we look at something, each eye sees it from different *angle. Our eyes send the two pictures to our brain, and the brain puts them together. The small difference between the picture from the right eye and the picture from the left eye make us see depth.
While watching 2-D films, we don’t have to wear the special glasses. We see the pictures in two dimensions, each eye get the same information. This is because there is only one way of watching it.
So the aim of 3-D technology is to get a different picture into each eye of the person. It uses two film *projectors. One *projects a left eye picture and the other projects a right eye picture. When we are in the cinema, we can see different pictures in each eye at the same time with the help of the 3-D glasses.
While watching 3-D films, we feel that we are actually in the same environment as the things we are watching. However, some people are against watching 3-D films. One of the reasons is the 3-D glasses makes the screen of the film or TV look darker. It is bad for eyes. What’s more, people with eye problems may get headaches if they spend too much time watching 3-D movies, because their brains need to work harder to “read” the pictures.  
Paragraph 3 mainly tells us __________.

A．how we see things in 3-D	B．how we watch the Olympic Games
C．how 3-D films are made	D．where we watch 3-D films or TV

When we watch a 2-D film, each of our eyes get ________ information.

A．no

B．different

C．dark

D．the same

Which is the following is right according to the passage?

A．We don’t have to wear 3-D glasses if we watch games in 3-D on TV.

B．The 3-D technology is based on the way the human ear and eye work.

C．All the people can have fun watching 3-D movies or TV for a long time.

D．3-D glasses make us see different pictures in each eye at the same time.

Why are some people against watching 3-D films? Because ____________.

A．they make them more excited or sadder

B．3-D glasses make the screen look darker

C．3-D films make all people get headaches

D．they dislike watching the Olympic Games