常见平行结构标志词：
平行结构中的成分A和B必须在语法形式上一致。例如：
.
She never drinks or smokes.
.
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He walked across the street and into the school.
.
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My sister is a dancer but her parents are teachers.
.
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Jacob speaks slowly and clearly.
.
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Prince William loves Kate Middleton not because of her beauty but because of her intelligence.
.
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Seeing is believing. =To see is to believe.
.
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Obama would either campaign for the president or campaign for the governor. .
Obama would campaign either for the president or for the governor.
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Obama would campaign for either the president or the governor.
.
例题讲解
1. To attempt acomprehensive mapping of the human genome is undertaking an
extremelyambitious project.
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genome is undertaking
.
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genome is to undertake
.
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genome undertakes
.
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genome , it undertakes
.
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genome, thus undertaking
.
解析：选B。根据平行结构句式Todo is to do，只有B选项满足这个平行结构的标准。A 选项犯的是todo is doing这样的错误，不定式不能和动名词构成平行结构。C选项句意错误。D选项it指代不明，句意模糊。E选项句子结构不完整，没有谓语动词。
2. A fineorchestral performance will exhibit the skills of the musicians, their abilityto
work as an ensemble and how he or she responds to the conductor.
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how he or she responds
.
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how to respond
.
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their responding
.
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their responses
.
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they respond
.
解析：选D。根据未划线部分的提示，可以判断原句应该是由and连接的平行结构。根据平行结构中的成分必须在语法形式上一致的原则，可以明显看出theskills…, their ability…
and how he or she responds…是不平行的，因为前两个成分是名词，而后一个成分是句子。所以只能选择D选项的名词theirresponses，这样才能跟前面的theskills和their ability构成平行结构。
小结
考生一定要记背常见平行结构标志词。在考试中首先迅速敏锐地发现这些标志词，然后确认句子中的成分在语法形式上是否一致，这样就能快速准确地解题。
上海新托福精讲班多少钱？
一、整体情况
培训对象：英语基础薄弱大学生或未接触过托福考试的高中生
培训目的：通过对托福基础听说读写的巩固及强化训练，帮助学员提高托福基础和应试技巧，
顺利通过考试。
目标分数：80-90分
课程时长：根据学员需要而定
课程学费：依照学员学习水平而定
二、课程安排
课程课程：主讲托福词汇、托福语法、托福听力、托福阅读、托福口语、托福写作；辅导课程：梳理课程知识，解疑答惑，查漏补缺；
测评课程：托福全真模考及考试分析点评；
三、模考安排
第一次：课程中间，安排一次托福全真模拟考试及点评
第二次：课程结束，安排一次托福全真模拟考试及点评
备注：除以上安排，学员结课后可根据自己的考试时间自行预约TPO小站模考
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