since作为从句引导词，可以引导时间、原因或条件从句。
It is since we implemented the new management strategy that our company has seen a steady increase in profitability.自从我们实施了新的管理策略以来，我们公司的盈利能力稳步增长。
It is since the invention of smartphones that communication has become much more convenient and instantaneous.自从智能手机的发明以来，沟通变得更加便捷和即时。It is since moving to a new city that I have been able to explore different cultures and broaden my horizons.自从搬到新城市以来，我能够探索不同的文化并开阔我的眼界。
It is since I started exercising regularly that I have noticed significant improvements in my overall health.自从我开始定期锻炼以来，我注意到我的整体健康状况有了显著的改善。这个句型适用于强调时间或事件对当前情况的直接影响或导致的结果。它可以用来表达个人经历、变化的原因、进步和成就等。
it is since的意思
It is since 表示过去某个时间开始，一直持续到现在的一段时间。例如：“It is since last year that I started learning French.”（自从去年开始，我就开始学习法语。）这句话强调从去年到现在一直在进行法语学习。
It is since 表示某个时间点或事件是导致当前情况或状态的原因。例如：“It is since I started eating healthier that I have been feeling more energetic.”（自从我开始吃得更健康以来，我感觉更有精力。）这句话强调健康饮食是导致目前有更多精力的原因。