on the off-chance搞不好会
infinitesimal off-chance pinpoint teeny极微的
Off-hand Critical Chance失手几率
PHRASE（习语） If you do something on the off-chance, you do it because you hope that it will succeed, although you think that this is unlikely. 怀着渺茫希望的
He had taken a flight to Paris on the off-chance that he might be able to meet Francesca.
他搭飞机去了巴黎，怀着遇到弗朗西丝卡的渺茫希望。