纵深

前线作战部队迅速撕开防线，向敌方纵深防御地带发起猛烈冲击。

qián xiàn zuò zhàn bù duì xùn sù sī kāi fáng xiàn, xiàng dí fāng zòng shēn fáng yù dì dài fā qǐ měng liè chōng jī.

The frontline combat troops quickly tore apart the defense line and launched a fierce attack on the enemy's deep defense zone.