先理解标题，推测文章内容：Light Night，Dark Stars.没有生词，明亮的夜晚，昏暗的星空。只是看题目，还不易推测出文章的主要内容，因此，要快速浏览全文，看能否找到出现频率较高的词或短语，它们有可能就是文章的核心！大家看到了我用黑线标出了出现频率最多的短语：light pollution.所以可以推测文章的内容和光污染有关。
接下来判断所给5题的题型，我们发现1至4都是细节题，因此只需要找到关键词逐一回答即可。而第5题是主旨题，而且是最后一题，所以要等文章读完后最后做。
1. When can people see 14000 stars?
A When they have a fairly good telescope当他们有一个非常不错的望远镜．
B When they are in a large city当他们在大城市时．
C When the night sky is clear of clouds，moonlight and artificial lights当夜空中没有云、月光和人造灯光时．
D When the night sky is without haze and fog当夜空没有阴霾和大雾时．
分析：关键词很容易找14000 stars，在第一段出现了该词：
Thousands of people（数以千计的人） around the globe （世界上）step outside（走出去） to gaze at（凝视） their night sky．On a clear（晴朗的） night， with no clouds， moonlight，or artificial （人造的）lights to block（遮挡、挡住） the view，people can see more than 14，000 stars in the sky(答案C)，says Dennis Ward，an astronomer（天文学家） with the University Corporation for Atmospheric Research(UCAR)in Boulder，Colo．But when people are surrounded (被。。。包围)by city lights．he says，they’re lucky to see 150 stars．
补充：请注意短语：be clear of sth: 无阻碍、障碍、危险
如：Wait until the road is clear of traffic before crossing.(等到路上没车时再过马路。)
2．Which of the following statements(叙述) is NOT related to（同。。。有关） light pollution?
A A haze of light is formed from artificial lights such as streetlights and building lights（阴霾的光是由人造光而形成的，如路灯和建筑物的光）．
B Lights from different sources in the city stream into space and illuminate the night sky来自于不同来源的光进入太空并照亮了夜空．
C The night sky is illuminated by the lights from big glowing cities in the night夜空由晚上大城市发出的光照亮．
D Stargazing（star gazing观望星星） becomes difficult because there is a layer of haze in the air由于空气中有一层霾，所以观望星星变得困难．
分析：本题的关键词是light pollution，而且按照题目的题号应该在文章的前面，所以从第二段找找看：
If youve ever driven toward a big city at night and seen its glow from a great distance（答案C）， you’ve witnessed（见证、目睹） light pollution．It occurs when light from streetlights，office buildings，signs，and other sources streams into space and illuminates the night sky（答案A，B表述）．This haze of light makes many stars invisible to people on Earth．Even at night，big cities like New York glow from light pollution， making stargazingdifficult（请注意这句话并不是答案D，他们不同，该句是说：甚至在晚上，许多像纽约这样的大城市所产生的灯光使观望星星变得困难。）所以，D的表述同光污染没有关联。
3.Does the writer think growing cities affect astronomers’ work?Why does he think so?
A Yes．Because the once dark rural areas are polluted by lights因为曾经黑暗的乡村地区被光污染了．
B No．Because they Call still see stars in rural areas．
C.Yes．Because rural areas are not a good place for astronomers to study stars因为乡村地区不是一个好的研究星星的地方。
D. No. Because faint light given off by stars call still be seen on a clear night
分析：题目是说：不断扩大的城市会影响天文学家的工作吗？为什么他会这样认为？
在A答案中我们可以看到线索词：polluted 和lights.所以，根据阅读的规律，只要和线索词有关的答案，多半就是最终答案。如果大家想检查答案是否正确的话，也可以带着关键词astronomers 去找答案：
Hazy skies also make it far more difficult for astronomers to do their jobs.
通过对句子的分析，排除答案B，D.留下A，C.在接下来的段落中可以对答案加以判断：
Cities are getting larger．Suburbs（郊区） are growing in once dark，rural areas．Light from all this new development is increasingly obscuring(使。。。变得模糊) the faint （微弱的）light given off by distant stars．And if scientists cant locate（确定。。。的位置） these objects，they can’t learn more about them．