不期而然

Explanation: Period: hope; natural: so. Do not want this, but even so. That surprising. 　　Usage: Contraction type; as predicate, adverbial; describe something unexpected 　　Source: Sung-mao "Wild-off series": "cover their daily reading Waizu Sima Qian in mind that it aims to occur in the word, however unexpected." 　　Examples: Between mountains and rivers, red county Divine, the far and not second, unexpected however. (Qing Wu Research people "confused world order") Thesaurus:  Happen unexpectedly, upset, unexpectedly, Out its take at advantage, against expectation, s unpreparedness, The enemy accident