1. The antitail is a distinct feature of comets, which differentiates them from other celestial bodies.

反尾巴是彗星的一个独特特征，它使彗星与其他天体区分开来。

2. The antitail of the insect serves as a defense mechanism, deterring predators from attacking from behind.

昆虫的反尾巴作为一种防御机制，阻止捕食者从背后袭击。