I don’t understand ____ believe him.

i don't know____to believe him 改为复合句：I don't understand him I don't understand()()() I don\'t believe him,so I don\'t believe in i don't understand I don't believe him （）he says. I don't believe I don\'t believe Don't you believe ____? Sorry,I don't understand . afraid i don't understand I don't understand you. I still don't understand