1. The protestors used megaphones to amplify their chants and demands.
抗议者使用扩音器来放大他们的口号和要求。

2. The coach used a megaphone to communicate with the players on the field.
教练用扩音器与场上的球员交流。

3. The tour guide used a megaphone to make sure everyone could hear her explanations.
导游用扩音器确保每个人都能听到她的解释。

4. The lifeguard used a megaphone to warn swimmers of the dangerous currents.
救生员用扩音器警告游泳者危险的洋流。

5. The teacher used a megaphone during the field trip to keep the students together.
老师在实地考察时使用扩音器让学生集中在一起。

6. The event organizers handed out megaphones to volunteers to help with crowd control.
活动组织者把扩音器发给志愿者帮助控制人群。