宾语从句中if,weather,that,what,who是怎么来的

这是宾语从句的引导词
if,weather是否的意思,来自一般疑问句变成的宾语从句；
that陈述句变成的宾语从句.
what,who特殊疑问句变成的宾语从句.
I don't know if he is right.
I know that he is right.
I want to know who is right.