阵 (zhèn): measure word for bursts, periods

Before the battle began, the general carefully examined the map and studied the enemy's formation.

The soldiers formed a neat battle formation and waited for the commander's order.

Facing the enemy's fierce attack, our army had to adjust its battle line and retreat to a safer place.

The football coach set up a defensive counter-attacking formation based on the opponent's characteristics.

The enemy suddenly changed their formation and attempted to outflank us from both sides, trying to surround us.