《左传·隐公·隐公十年》
夏季五月，羽父事先会合齐僖公、郑庄公，进攻宋国。
夏五月，羽父先会齐侯、郑伯伐宋。
In the fifth month of summer, Feather Father met secretly with Duke Xi of Qi and Duke Zhuang of Zheng and attacked Song.
<s>[INST] Transpose the following Modern Chinese text into Classical Chinese: 夏季五月，羽父事先会合齐僖公、郑庄公，进攻宋国。 [/INST] 夏五月，羽父先会齐侯、郑伯伐宋。</s>
Transpose the following Modern Chinese text into Classical Chinese: 夏季五月，羽父事先会合齐僖公、郑庄公，进攻宋国。
user
夏五月，羽父先会齐侯、郑伯伐宋。
assistant