it作形式主语为避免主语冗长,句子头重脚轻,经常用it作形式主语,主语从句放在后面作真正的主语
Itiscertainthathewillsucceed
Itisnotknownwhetherhewillgothere
Ithasnotbeendecidedyetwhenthey’llstarttheproject
“It”isusedasemptysubject
Itis+名词+从句Itisafactthat…事实是…Itisanhonorthat…非常荣幸Itiscommonknowledgethat…是常识能获邀参加你们的婚礼真是不胜荣幸风就是流动的空气,这是常识可惜他由于一个拼写错误没有得满分It’sagreathonorthatIhavebeeninvitedtoyourwedding
It’scommonknowledgethatwindismoving/flowingair
It’sapitythathedidn’tgetfullmarksbecauseofaspellingmistake
Itis+adj
+从句It’scertainthat…肯定…Itispossiblethat
很可能……Itisunlikelythat
不可能……Itisobviousthat…很明显…Itisnecessary\important\natural\
that…*_________________(很可能)shewillcomebacktomorrow
*_________________(很明显)thismeasureiseffective
+(should)+do…ItispossiblethatItisobviousthat句型2
另注意在主语从句中用来表示惊奇、不相信、惋惜、理应如此等语气时,谓语动词要用虚拟语气“