(2002, text 2)
Despite a spell of initial optimism in the 1960s and 1970s when it appeared that transistor circuits and microprocessors might be able to copy the action of the human brain by the year 2010, researchers lately have begun to extend that forecast by decades if not centuries.
句子结构：
让步状语：Despite a spell of initial optimism in the 1960s and 1970s
定语从句：when it appeared （修饰限定前面的1960s and 1970s）
主语从句：that transistor circuits and microprocessors might be able to copy the action of the human brain by the year 2010 （前面的it作形式主语，that从句是真正的主语）
主干：researchers lately have begun to extend that forecast by decades if not centuries
词汇学习
spell [spel] v. 拼写；招致，导致； n. 一段时期；魔法，咒语
a spell of 一段时期
initial [ɪ'nɪʃ.əl] adj. 开始的，最初的
optimism ['ɒp.tɪ.mɪ.zəm] n. 乐观；乐观主义
appear [ə'pɪər] v. 出现；呈现；显现
transistor circuits 晶体管电路
microprocessor 微处理器
extend [ɪk'stend] v. 延伸，扩大，延长
forecast ['fɔ:.kɑ:st] v. n. 预报，预测
词汇拓展
1. 预测：predict, foretell, foresee
原文重现
Despite a spell of initial optimism in the 1960s and 1970s //when it appeared //that transistor circuits and microprocessors might be able to copy the action of the human brain by the year 2010, researchers lately have begun to extend that forecast by decades if not centuries.
句子翻译
尽管在20世纪60年代和70年代有过一段最初的乐观时期，那时候晶体管电路和微处理器的发展似乎使人们相信到2010年就能复制人脑，但最近研究者已经开始将这个预测向后推迟了数十年，甚至数百年。
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