例句：
1、部隊已準備發(fā)起攻擊。
The troops took up offensive positions.
2、部隊從淪陷的城市安全撤出。
The troop made good their retreat from the occupied city.
3、部隊在小山上集合。
The troops mustered on the hill.
4、部隊已經(jīng)撤出危險地帶。
The troops have been withdrawn from the danger area.