阅读理解。 Students and professionals can al

题目：

阅读理解。

     Students and professionals can all benefit from reading scholarly research. While many works may be of

a technical nature, some of the best research is published in professional journals. While not all journals get

published on the Internet, the trend toward the electronic format is growing. You probably also have free

access to some of the online sources outlined below, but many don't know where they can consult online

sources when in need of excellent research.

      Science

     The journal Science is perhaps the most prestigious science journal. This journal is also well known

enough to be featured on media outlets. It has all the latest news. Science is also interested in scientific policy,

and frequently publishes articles that report the achievement of technology and science in general. Free partial

access is available after registration.

      Proceedings from the National Academy of Sciences (PNAS)

     The world famous scholar reviewed journal has its articles and reviews on their website. While reading

the abstracts of articles is free, PNAS charges for downloading the entire article in full. There is also an option

for paying a flat rate to view several articles for a week-long period. There are some "open access" articles

which are available for download free of charge. Nature Nature is another popular and famous journal. Nature

has a wide approach publishing scientific papers on a wide variety of topics.

     Nature in fact is considered interdisciplinary (各学科间的), going beyond its name which would seem to

show it only belongs to the natural sciences. Nature is aimed at researchers and academics, but readers can

find out about major breakthroughs through summaries and other notes that appear in this weekly publication.

     While there is an effort to provide so-called "open access", it is at the moment limited. Students and those

with academic access can access these major journals for free because of contractual relationships.

1. What do we know from the passage?

A. All the best research is published in professional journals.

B. Fewer and fewer journals will be put out online in the future.

C. Reading professional journals is quite helpful for students.

D. A small number of the online sources can be attained for free.

2. The underlined word "prestigious" is the closest in meaning to ______.

A. complicated

B. famous

C. special

D. instructive

3. According to the passage, it's free of charge for us to download ______.

A. the entire article of the PNAS in full

B. the entire journal Nature

C. one article of the journal Science

D. "open access " PNAS articles

4. This passage mainly tells us _______.

A. how to publish professional papers

B. about a few academic magazines in the world

C. about free access to some of the online sources

D. which journal is most famous in the world