精选优质文档-倾情为你奉上2012届高考一轮复习语法专项一:句子成分、简单句、并列句和复合句一、句子成分(一)句子成分的定义:构成句子的各个部分叫做句子成分。句子成分有主要成分和次要成分;主要成分有主语和谓语;次要成分有表语、宾语、定语、状语、补足语和同位语。(二)主语:主语是一个句子所叙述的主体,一般位于句首。但在there be结构、疑问句(当主语不疑问词时)和倒装句中,主语位于谓语、助动词或情态动词后面。主语可由名词、代词、数词、不定式、动名词、名词化的形容词和主语从句等表示。例如:During the 1990s, American country music has become more and more popular.(名词)We often speak English in class.(代词)One-third of the students in this class are girls.(数词)To swim in the river is a great pleasure.(不定式)Smoking does