“在这以前”常见的英文表达有 before this、prior to this 或 before that time（若“这”指代特定时间点，用“that time”更明确） 。
Before this：是比较直接、口语化的表达。例如：Before this, I had never been to a big city.（在这以前，我从未去过大城市。）
Prior to this：相对更正式、书面一些。例如：Prior to this event, we had no idea about the seriousness of the situation.（在这件事发生以前，我们完全不知道情况的严重性 。）
Before that time：当需要明确“这”所指的具体时间点时使用。例如：Before that time, I had always lived in the countryside.（在那以前，我一直住在乡下 。）