问题 阅读理解

三:阅读理解(共25小题;每小题2分,满分50分)  

Eye Facts

There are many commonly held beliefs about eyesight that are not proven facts. For example, some people believe that wearing glasses too soon weakens the eyes. But there is no evidence to show that the structure(结构)of eyes is changed by wearing glasses at young age. Wearing the wrong glasses, however, can prove harmful. Studies show that for adults there is no danger, but children can develop loss of sight if they have glasses unsuitable for their eyes.

We have all heard some of the common myths about how eyesight gets bad. Most people believe that reading in weak light causes poor eyesight, but that is untrue. Too little light makes the eyes work harder, so they do get tired and strained. Eyestrain also results from reading a lot, reading in bed, and watching too much television. However, although eyestrain may cause some pain or headaches, it does not damage eyesight in the long term.

Another myth about eyes is that they can be replaced, or transplanted from one person to another. There are close to one million nerve fibers(神经纤维)that connect the eyeball to the brain; as of yet, it is impossible to connect them all in a new person. Only certain parts of the eye can be replaced. But if we keep clearing up the myths and learning more about the eyes, someday a full transplant may be possible!

1. This passage is mostly about __________.

A. different types of eye problems        B. myths about eyesight

C. beliefs of eye doctors           D. eye transplants

2. One cause of eyestrain mentioned in the passage is __________.

A. wearing glasses too long      B. suffering from pain or headaches

C. reading in poor light         D. reading before going to bed

3. From the passage we can conclude that __________.

A. doctors are still learning things about eyesight

B. wearing wrong glasses is less harmful to adults

C. eye transplants have been performed successfully

D. people should not wear glasses at young age

答案

小题1:B

小题2:C

小题3:A

单项选择题
单项选择题

Current Group, a Germantown-based technology firm, has taken over an ordinary looking house in Bethesda and turned it into a laboratory for smart-grid technology, the system the company believes will bring the nation’s electricity grids into the digital age.

In the front yard stands a utility pole hooked up to a special transformer that connects the power lines to high-speed Internet. Hundreds of sensors attached to the lines monitor how power flows through the home. That information is then sent back to the utility company.

The process lets a utility more efficiently manage the distribution of electricity by allowing two-way communication between consumers and energy suppliers via the broadband network on the power lines. Based on data they receive from hundreds of homes, utilities can monitor usage and adjust output and pricing in response to demand. Consumers can be rewarded with reduced rates by cutting back on consumption during peak periods. And computerized substations can talk to each other so overloaded circuits hand off electricity to those that have not fully loaded, helping to prevent blackouts.

Some utility companies have launched initiatives to give consumers data about their energy consumption habits in an effort to lower energy bills. Smart-grid technology takes such programs further by automating electricity distribution, which would make grids more reliable and efficient.

By partnering with utilities, the company hopes to tap into $4.5 billion in stimulus grants intended to encourage smart-grid development. When he announced the funding, President Obama pointed to a project in Boulder, Colo. , as an example of a successful smart-grid experiment. Current is one of the companies working on the project.

Current’s chief executive Tom Casey believes the technology will help utility companies better distribute electricity produced by renewable resources, such as solar panels or wind farms. " A smart grid’s system can be paired up with the renewable resources so that when the renewable source is varying, the overall load can be varied as well, " Casey told the House Select Committee on Energy Independence and Global Warming. " This will reduce or eliminate the need for backup coal or gas-based power generation plants. \

For smart-grid technology to work, which of the following is a must()

A. The front yard of a house with a tall wooden pole

B. A huge hook that can connect power lines together

C. High-speed Internet access and Internet services

D. Many monitors through which power flowing can be seen