bus
The Spanish word 'obús' does not mean 'bus' in English. It is a noun used in military context usually referring to a kind of artillery. In English, this term would be translated as 'howitzer' or 'mortar'. The correct Spanish term for 'bus' is 'autobús'.
The enemy launched a shell during the battle.
In this context, 'obús' is used to refer to an artillery shell. The phrase describes a common wartime situation, where the enemy launches an artillery shell during a battle.
The shell made a big hole in the ground.
None
They found an unexploded shell on the battlefield.
In this sentence, 'obús' refers to an unexploded artillery shell found on a battlefield. It describes a potential danger in locations where conflict has taken place, as unexploded ordinance can still pose a serious threat.