主语从句 句型： It is +名词+从句 It is a fact that… 事实是…… It is good news that … ……是好消息 It is a question that … ……是个问题 It is common knowledge that … ……是常识 类似的名词还有：a pity；a wonder；a good thing； no wonder； surprise等. 例如：It is a mystery to me how it all happened. 这一切是怎么发生的是个谜. It is common knowledge that the whale is not a fish. 鲸鱼不是鱼,这是常识. It is no surprise that Bob should have won the game. 鲍勃会赢得这场比赛,这不足为奇.
