Where on Earth are you? Navigators (导航员) use lines of latitude and lines of longitude to locate places. Lines of latitude run east and west around Earth. On a map or globe, these lines appear as running sideways or horizontally. Lines of longitude run north and south around Earth. These lines go up and down or vertically on a map or globe. These lines create an imaginary graph paper on the Earth. They make it possible to find an absolute, or exact, location on Earth. They even allow us to give an absolute location to a place out in the middle of the ocean.
Lines of latitude tell us how far north or south of the Equator we are. Sailors have used primitive navigation tools, like astrolabes, since ancient times. The astrolabe uses the sun and stars to find an approximate location. Using such tools, they have been able to approximate their distance from the equator. Although their instruments may not have been the high quality we have now, they were incredibly accurate (精确) for their time.
Lines of longitude tell us how far east or west of the prime meridian (本初子午线) we are. Sailors constantly looked for new ways to increase their navigation skills. Still, it wasn’t until the 18th century that they were able to measure degrees of longitude. They would have been very envious of the technology available to us today.
When we use lines of latitude and longitude together, we can get a very precise location. If we want to identify the absolute location of a point, we look where the latitude and longitude lines cross nearest to that point. We use the coordinates (坐标) for that point as its address. Many maps today include degrees of latitude and longitude.
小题1:______ make it possible for people to find an exact place on Earth.
A．Latitudes
B．Longitudes
C．Navigators
D．Sailors小题2:The second paragraph mainly talks about _______.
A．the function of latitude
B．the use of the equator
C．the invention of astrolabe
D．the high quality instruments小题3: Why do maps include degrees of latitude and longitude?
A．To help trade expeditions.
B．To locate a precise place.
C．To cross the lines of the nearest point.
D．To identify how far a place is.小题4:The best title for this passage is ____________.
A．The map and the globe
B．Latitude and longitude
C．The equator and the prime meridian
D．Absolute coordinates
小题1:C
小题2:A
小题3:B
小题4:B
题目分析：文章介绍什么是经度和纬度，通过经度和纬度可以准确的找到地球上的位置。
小题1:细节题：从第一段的句子：Navigators (导航员) use lines of latitude and lines of longitude to locate places. Lines of latitude run east and west around Earth. 可知是导航员人们知道自己的位置。选C
小题2:段落大意题：从第二段的句子：Lines of latitude tell us how far north or south of the Equator we are. 可知这段讲的是纬度的功能。选A
小题3:细节题：从最后一段的句子：When we use lines of latitude and longitude together, we can get a very precise location.可知使用经度和纬度可以准确的定位。选B
小题4:主旨题：文章介绍什么是经度和纬度，它们的作用。是围绕经度和纬度展开的。选B
点评：本文考查细节题为主，细节题可以在文章中直接找到与答案有关的信息或是其变体。搜查信息在阅读中非常重要它包括理解作者在叙述某事时使用的具体事实、数据、图表等细节信息。在一篇短文里大部分篇幅都属于这类围绕主体展开的细节。做这类题一般采用寻读法即先读题，然后带着问题快速阅读短文，找出与问题有关的词语或句子，再对相关部分进行分析对比，找出答案。