I hear sirens. I wonder if something happened. Maybe someone got hurt or is sick.
子供と部屋でその音を聞いた時に、"I hear sirens. I wonder if something happened. Maybe someone got hurt or is sick." と表現することで、「救急車か消防車のサイレンが聞こえるね。何かあったのかな。誰か怪我とか病気したのかもしれないね。」という意味の英語になります。
同じ状況で使える他の表現:
Do you hear the emergency vehicles? There must be an incident.
That's the sound of an ambulance or fire truck. Something serious must have happened.