like clockwork idiom (also (as) regular as clockwork)
非常有规律;极为准时
very regularly, or at exactly the planned times
Since the recent improvements to the service, the buses are running like clockwork. 最近，自从改进服务后，公交车运行得非常准时。
My daughter always calls me every Friday evening, (as) regular as clockwork. 我女儿总是每星期五晚上给我打电话，非常准时。