From Wang Ling's poem 《寄介甫》 (Northern Song): '终见乘桴去沧海,好留余地许相依' — 'one day I shall sail away on a raft; leave me some space for us still to lean on each other'. Originally about emotional closeness, now about practical and rhetorical margin.
usage
Essential in Chinese communication culture — commitments, promises, and criticisms should leave 余地 for future adjustment or for preserving 面子 (face). Strongly advised in business and diplomatic language.
