Nowadays, many children spend hours a day looking at computer screens or other digital (数码的) products. Some eye care doctors say all the screen time has caused more children to have what they call computer vision syndrome (视力综合症).
Nathan Warford is an optometrist in the US. He says he has seen more children having eye problems. “More children come into my office because their parents have noticed that they have headaches (头疼)or red eyes, or because their degree of short-sightedness appears to be increasing (增加)very fast and they’re worried,” he said.
Dr. Warford says part of the problem is that even if their eyes start to feel uncomfortable or they start to get a headache, some children don’t tell their parents, because they don’t want their games or the computer to be taken away. Another part of the problem is that people blink (眨眼睛) less often when they look at the screen.A person who uses a computer or a digital product blinks about a third as much as we normally(正常地) do in everyday life. If eyes can’t stay wet or are too tired, they will not be protected like normal.
Which of the following may be caused by too much screen time?

A．Having wet eyes.

B．Having headaches.

C．Having small eyes.

D．Having a toothache

Why don’t some children tell their parents when their eyes start to feel uncomfortable?

A．They think it is not serious.

B．They want to continue playing computer games.

C．They don’t want their parents to worry.

D．Their parents don’t care about them.

People blink about   as they normally do when they use computers.

A．a third as much	B．two thirds as much
C．half as much	D．as much

From the passage, we can learn that    .

A．children should blink as much as possible

B．tears can’t protect eyes

C．blinking is good for eyes

D．It’s useless to blink.

What is the passage mainly about?

A．Some information about the latest digital products.

B．Dr. Warford’s experience of working out eye problems.

C．Eye problems in children caused by using digital products.

D．It’s bad to use computers .