私约降 (私約降) sī yuē xiáng

sī yuē xiáng phrase a secret agreement for surrender
Domain: Literary Chinese 文言文
Notes: Quote: from the 漢書 “Book of Han”, volume 95 by 班固 Ban Gu 32-92 CE (Amies 2021 tr.; see also tr. Wylie 1880, p. 84)