一饮而尽 toss off the cup; down the hatch!; drain the cup with one gulp; drink clean at one gulp; drink off [up] at [in] a [one] draft [draught]; drain the cup [glass; bowl]; drink the whole in one draft [breath]; drink up in one swallow; empty one's cup in one gulp; swallow at one gulp; take one's drink at a gulp; toss one's glass back at a gulp
一饮一啄 every bite and every sip is preordained.; live in conformity to nature and be leisurely and carefree; one cannot get what is denied him by desting on matter how hard he tries