-I just have no idea ( ) that made liu huan such a famous si

Dno idea 后面句子构成idea的同位语。这个同位语又是由what引导的主语从句担当的。在这个主语从句里面又包含了强调句型,确实够复杂的。把it was that 去掉还原看, what made liu huan such a famous singer这是一个完整句子,并且构成idea同位语。what 可引导主语从句和宾语从句,就这两种。