What 和that 在名词性从句中的用法区别What 和that 都可以引导名词性从句。一在引导名词性从句时，从属连词that一般要注意三个不（three nos）：1不省略（no ellipsis）当从属连词that引导主语从句、表语从句和同位语从句时，that不省略。Eg. 1) That he was able to come made us happy. (That 引导主语从句不可省略)2)The truth is that I didnt go there. (that引导表语从句不可省略)3)The news that our team has won is true. (that引导同位语从句不可省略)但在非正式文体中that 引导宾语从句时可以省略，除下列两种情况外：that在宾语从句中不能省略的情况. (1). 在主+谓+it(形式宾语)+宾补+that， 从句(真正宾语) 的句型中不省略. Eg: 4) He made it quite clear that he preferred to study
