在骚乱中，警察举起他的盾牌来阻挡飞来的碎片。

The police officer raised his ___shield to block incoming debris during the riot.

在古代战斗中，战士依靠剑和盾牌进行攻防。

In ancient battles, warriors relied on a sword and ___shield for both offense and defense.

现代防暴装备通常包括透明的聚碳酸酯盾牌，以提供更好的视野和防护。

Modern riot gear often includes a transparent polycarbonate ___shield for better visibility and protection.