患难之交

Explanation: Attn: friendship, friends. Together experienced the hardships of friends. 　　Usage: Partial official; as predicate, object; means made good friends through the difficult 　　Source: Ming Chiao Hung "bundle language recommend Yutang": "Chung Chen and Wen held in Wuchang, because adversity, Ne black potter to a text." 　　Examples: They are ~, mutual understanding, like brothers. 　　Riddle: Patients Thesaurus:  a friend until death, ties between friends willing to sacrifice even life for each other, The world is but a little place, after all., Sworn brothers and sisters The contract, Very friendly Heart, click, Qingshenyihou, Yi Results sworn brothers and sisters Antonym Group:  only slightly acquainted with (a person), have met only once, Side of the Ya, To sever friendship Sub-Block, Guan Ning to sever friendship