将“date back"翻译成中文

The case dated back to the end of 1997.

本案发生的时间要追溯到1997年年底。

The deteriorating environment dated back to the early 1990s.

环境的逐渐恶化可回溯至1990年代初。

Ethiopia, as is well known, has unique cultural traditions whose origins date back to ancient times.

众所周知,埃塞俄比亚有着其起源追溯到古代的独特的文化传统。