Be 动词和do 一起使用构成进行时,如what are you doing?
你可以把 do you think,看成一个插入语就行了。换句话可说成who is the funniest actor? in your viewpoint.
这是个主语从句,who do you think是全句的从句,它有自己的谓语动词do。它做全句的主语,is则是全句的谓语动词。
who do you think is the funniest actor?
这里的do you think 是插入语~~~可以省略的,不做句子成分,所以这句话可以看成是who is the funniest actor?
who is the funniest actor?be动词可以省略