Generally speaking, Chongqing University of Posts and Telecommunications has two chances to defend graduation thesis. The first defense is a formal defense. If a student fails to reply for the first time, he can reply for the second time within the specified time. The second defense is usually called supplementary defense or re-defense. Students need to make corresponding improvements and perfection on the basis of the first defense, submit their papers again and defend in the second defense. If students still fail to pass the second defense, they need to resubmit their papers and take part in the defense again. In short, students have two chances to defend their graduation thesis. If you fail, you need to re-prepare your thesis and re-apply for defense.