3．
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 images（影像）from the screen look like they are there in the room with you．
3-D，means having three dimensions （維度）：width，height and depth.3-D technology is based on the way the human brain and eyes work．Because the pupils of a person's eyes are about 6.5cm apart，when we look at something，each eye sees it from a different angle （角度）．Our eyes send the two images to our brain，and the brain puts them together．The small difference between the image from the right eye and the image from the left eye allows us to see depth．
When we view media such as pictures and television in two dimensions，each eye gets the same information．That is because the image has no real depth，and there is only one way of viewing it．
So the goal of 3-D technology is to get a different image into each eye of the viewer．It uses two film projectors（投射器）．One projects a left eye image and the other projects a right eye image．The 3-D glasses allow us to see a different image in each eye．
While watching 3-D films，we feel that we are actually in the same environment as the things we're watching．However，it also has its disadvantages．The 3-D glasses make the screen look darker．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 images．
71．A special pair ofCis needed when you watch 3-D movies．
A．chopsticks
B．gloves
C．Glasses
72．The underlined word"pupils"in the third paragraph probably meansB in Chinese．
A．紫色的
B．瞳孔
C．眉毛
73．When a person watches a 2-D film，each of his eyes getsC information．
A．no
B．different
C．the same
74．People whoA can't watch 3-D TV too long．
A．have eye problems
B．can't walk
C．have hearing problems
75．Which of the following is TRUE？A
A.3-D technology is based on the way the human brain and eyes work．
B．A 3-D film needs to use one film projector．
C.3-D glasses make the screen look brighter．
