【歃血为盟】〖shà xuè wéi méng〗[smear the blood as a sign of the oath -- an old Chinese practice; lick blood and swear; pledge each other in wine in which blood has been mixed; smear one's lips with its blood in token of one's oath]

歃会邦交结友好，

血涂嘴唇缔约牢。

为国为民谋幸福，

盟山誓海和平保。

发誓订盟。Swear an alliance.同：对天盟誓。反：口血未干。