请允许我在此告辞，有急事要处理。

Qǐng yǔnxǔ wǒ zài cǐ gàocí, yǒu jíshì yào chǔlǐ.

Please allow me to take my leave here; there is an urgent matter to attend to.

毕业典礼结束后，学生们向校长告辞。

Bìyè diǎnlǐ jiéshù hòu, xuéshēngmen xiàng xiàozhǎng gàocí.

After the graduation ceremony, the students said goodbye to the principal.

在晚宴结束时，宾客们纷纷告辞。

Zài wǎnyàn jiéshù shí, bīnkè men fēnfēn gàocí.

Guests bid farewell one after another as the evening banquet concluded.