“在剧院”常见的英文表达是 at the theater（美式英语）或 at the theatre（英式英语） 。例如：
We're going to meet at the theater at 7 p.m.（我们晚上7点在剧院碰面。 ）
They sat quietly at the theatre, enjoying the performance.（他们静静地坐在剧院里，欣赏着演出。 ）