1. Lewis and Clark journeyed into the American wilderness to find out what the U.S. had acquired when it purchased Louisiana, and the Appolo astronauts rocketed to the moon in a dramatic show of technological muscle during the cold war. (2001. 阅读. 1. Text 4)

　　【译文】里维斯和克拉克在美国荒野中跋涉是为了找出美国购买路易斯安纳州后能得到的物产，而阿波罗号宇航员乘坐火箭飞往月球则以戏剧性的方式展示了美国冷战期间的科技实力。

　　【析句】句子主干是Lewis and Clark journeyed into the American wilderness to find out..., and the Appolo astronauts rocketed to the moon in a dramatic show of...。可以看出，主句是由and连接的两个并列句组成。前句主句中，to find out...是不定式作目的状语，what the U.S. had acquired作find out的宾语从句，而宾语从句中又包含when引导的时间状语从句。后句是个简单句，in a dramatic show of...用了介词短语作方式状语。

　　2. The issue of whether life ever existed on the planet, and whether it persists to this day, has been highlighted by mounting evidence that the Red Planet once had abundant stable, liquid water and by the continuing controversy over suggestions that bacterial fossils rode to Earth on a meteorite from Mars. (2001. 阅读. 1. Text 4)

　　【译文】关于火星上是否曾存在生命的问题，是否生命尚存活的问题，都得到了强调——一方面因为已经有大量的证据证明火星曾经拥有稳定的液态水，另一方面因为人们就关于陨石把细菌从火星带到地球上各种说法继续持有争议。

　　【析句】复合句。主句The issue of whether...,and whether...,has been highlighted by...and by...。主句主语the issue of后有两个并列的whether引导的宾语从句。by mounting evidence和by the continuing controversy over suggestions在主句中由and连接，为并列的方式状语。而且状语后各有一个that引导的同位语从句分别修饰mounting evidence和suggestions。

　　3. A more conclusive answer about life on Mars, past or present, would give researchers invaluable data about the range of conditions under which a planet can generate the complex chemistry that leads to life. (2001. 阅读. 1. Text 4)

　　【译文】对火星上过去或现在是否存在生命这一问题得出更具总结性的回答，给研究家们提供了宝贵资料，以研究一颗星球在何种条件范围内能够产生复杂的孕育生命的化学物质。

　　【析句】复合句。主句A more conclusive answer about...would give researchers invaluable data about the range of conditions, under which a planet can generate the complex chemistry作定语从句修饰conditions,而定语从句中又包含定语从句that leads to life修饰the complex chemisty.

(责任编辑：田学江)