it做形式主語(yǔ)用法大全

it做形式主語(yǔ)用法大全I(xiàn)t作形式主語(yǔ)常見(jiàn)句型動(dòng)詞不定式，動(dòng)名詞或主語(yǔ)從句作主語(yǔ)時(shí)，通常把它們放在謂語(yǔ)動(dòng)詞前，而用it作形式主語(yǔ)，放到句首，常見(jiàn)句型有：1.It+be+形容詞+主語(yǔ)從句，如：2.It+be+名詞詞組+主語(yǔ)從句，這類名詞有：afact,apity,ashame,anhonour，aquestion等，如：It’sapitythatyoumissedtheexcitingfootballmatch.3.It+be+過(guò)去分詞+主語(yǔ)從句，這類過(guò)去分詞有：announced,believed,expected,hoped,decided,reported,said,shown等，如：Itisreportedthat16peoplewerekilledintheearthquake.Itisnotdecidedwhowillgivetheoperationtothepatient.4.It+不及物動(dòng)詞(seem,appear,happen等)+主語(yǔ)從句,這類不及物動(dòng)詞有：appear,happen,seem等，如：Itseemedthathedidn’ttellthetruth.IthappenedthatIwasoutwhenhecalled.5.It+be+形容詞+forsb.）+動(dòng)詞不定式這類句型常用形容詞easy,difficult,hard,important,possible，wise等作表語(yǔ)，有時(shí)候?yàn)榱藦?qiáng)調(diào)不定式動(dòng)作的執(zhí)行者，常在不定式前加forsb，如：It’snecessaryfortheyoungtomastertwoforeignlanguage.Itisunwisetogivethechildrenwhatevertheywant.這類形容詞有：easy,difficult,hard,important,possible，wise6.It+be+形容詞+ofsb.+動(dòng)詞不定式，這類形容詞常是表示心理品質(zhì),性格特征的形容詞，如：kind,nicestupid,clever,foolish,polite,impolite,silly,selfish,considerate等。某人和這些形容詞可以構(gòu)成主系表結(jié)構(gòu)。如：It’sverykindofyoutohelpmewiththework.=Youarekindtohelpme.Itseemedselfishofhimnottosharehisdictionarywithothers.=Heseemedselfishnottosharehisdictionarywithothers.7.It+be+名詞詞組+動(dòng)詞不定式，如：Itisnotagoodhabittostayuptoolate.8.It+be+名詞或形容詞+動(dòng)名詞，這類名詞和形容詞常常是：good,nogood,nouse,awaste