1. A century ago, Freud formulated his revolutionary theory that dreams were the disguised shadows of our unconscious desires and fears; by the late 1970s, neurologists had switched to thinking of them as just “mental noise” -- the random byproducts of the neural-repair work that goes on during sleep. (2005. 阅读. Text 3)
　　【译文】一个世纪前，弗洛伊德阐述了革命性的理论，即梦是人们潜意识中欲望和恐惧经伪装后的预示；到了20世纪70年代末期，神经病学家们转而认为梦是“精神噪音”，即睡眠时进行的神经修复活动的一种杂乱的副产品。
　　【析句】整句话有两个分句，注意标点符号；的使用。第一个分句比较简单，是由主句Freud formulated his...theory和that引导的表语从句dreams were...fears组成；第二个分句中，句子主干是neurologists had switched to thinking of...as...,分号后的内容是插入语，进一步解释说明mental noise是什么，其中，the random byproducts...work后that引导定语从句修饰the neural-repair work。

　　2. And one leading authority says that these intensely powerful mental events can be not only harnessed but actually brought under conscious control, to help us sleep and feel better, “It’s your dream,” says Rosalind Cartwright, chair of psychology at Chicago’s Medical Center. (2005. 阅读. Text 3)
　　【译文】一名主要的权威人士说，梦这种异常强烈的精神活动不仅能被驾驭，事实上还可以有意识地加以控制，以帮助我们更好地睡眠和感觉。芝加哥医疗中心心里学系主任 Rosalind Cartwright说“梦是你自己的，如果你不喜欢，就改变它。”
　　【析句】复合句实际上是由两句话组成的，第一句话one leading authority says that...是间接引用，that引导says的宾语从句；to help us...better则作目的状语。第二句话It's your dream,says Rosalind...属于直接引用某人说话的内容，容易理解。

　　3. The brain is as active during REM (rapid eye movement) sleep -- when most vivid dreams occur -- as it is when fully awake, says Dr.Eric Nofzinger at the University of Pittsburgh. (2005. 阅读. Text 3)
　　【译文】匹兹堡大学的埃里克博士说，在出现清晰梦境的快速动眼睡眠中大脑和完全清醒时一样活跃。但并非大脑的所有部分都一样，脑边缘系统（“情绪大脑”）异常活跃，而前额皮层（思维和推理的中心地带）则相对平静大。
　　【析句】首先，整个长句都是Dr. Eric says的内容，属于间接引用。句子的主干是The brain is as active during REM as it is when awake，主要运用了as...as...“...和...一样”这一短语，两个分号之间when most dreams occur作插入语。