坐以待旦zuò yǐ dài dànsit waiting for the dayto dawn; remain awake (/seated/up) till daybreak(/dawn); sit up till dawn; stay up all night long
❍ 贾母等才得略略放心，只好～，叫凤姐去请宝钗安息。(《红楼梦》1272)She decided to sit up with him till dawn and sent Xifeng to urge Baochai to rest too.
❍ 幸而得之，～。(《孟子·离娄下》)...and when he was fortunateenough to master the difficulty,he sat waiting for the morning. 坐以待旦zuò yǐ dài dàn旦：早晨。坐着等到天亮。Remain awake till dawn. stay up all night long, sit up and wait for daybreak |