It做形式主语讲解复习课程.ppt

It做形式主语 It snecessaryfortheyoungtomastertwoforeignlanguage It sawasteoftimetalkingtoheranymore It sapitythatyoumissedtheexcitingfootballmatch 动词不定式 动名词 从句 形式主语 It作为形式主语的用法 当不定式 动名词 从句等用作句子主语时 为保持句子平衡 通常把真正的主语放在句末 而在句首使用形式主语it 拒绝是令人遗憾的 记住这一点是很重要的 It sapitytorefuse It sveryimprotanttorememberthis 一 代替动词不定式做形式主语 It be adj forsb todosth 此处adj 通常为描述事件的形容词 easy difficult hard necessary impossible important natural likely obvious useful useless dangerous 做某事是 It snecessaryforustomasteraforeignlanguage It be adj ofsb todosth此处adj 通常为描述人的形容词 kind nice rude cruel careless foolish stupid wise crazy 某人做某事 某人是 eg It sfoolishofyoutodriveacarafterdrinking It sverykindofyoutohelpmewithmyEnglish It be 名词词组 动词不定式eg Itisnotagoodhabittostayuptoolate 常见句型 Ittakes tooksb sometime moneytodosth Itisnogoodcryingoverspiltmilk Itisnousecastingpearlsbeforeswine 覆水难收 不要明珠暗投 对牛弹琴 构成如下结构 Itis nouse nogood notanygood notanyuse doingsth 二 代替动名词作形式主语 It be 名词词组 主语从句这类名词有 afact apity ashame anhonour aquestion asurprise commonknowledge eg It scommonknowledgethatpeoplecann tlivewithoutwater 三 代替从句做形式主语 It 不及物动词 that asif 从句这类不及物动词有 look seem appear happen occureg Itseemsthathedoesnottellthetruth Itistime thatsb v ed shoulddoEg It stimethatyouwenttobedIt stimethatyoushouldgotobed It snecessary impossible important naturalthatsb should doEg It simportantthatwe should keepthebalanceofnature It be adj that 从句 It be ed 过去分词 that 从句 Itissaidthat 据说 Itisreportedthat 据报道 Itissupposedthat 据推测 Itishopedthat 希望 Itiswellknownthat 众所周知 Itisgenerallyconsideredthat 普遍认为 Itissuggestedthat 有人建议 练习 把下列格局转换为it做形式主语的句子 1 Hewasrudetosayso 2 Tryingagainisofuse 3 Whenandwheretoholdthepartyhasn tbeendecided Itwasrudeofhimtosayso Itisofusetryingagain It