《宋史·本纪·卷九》
五月初一，交趾攻打边境。
五月乙未朔，交阯寇边。
On the 1st of May, Giao Chi attacked the border.
<s>[INST] Explain the meaning of this Classical Chinese passage in English: 五月乙未朔，交阯寇边。 [/INST] On the 1st of May, Giao Chi attacked the border.</s>
Explain the meaning of this Classical Chinese passage in English: 五月乙未朔，交阯寇边。
user
On the 1st of May, Giao Chi attacked the border.
assistant