leave oneself a way out; leave oneself an option; provide a passage for escape in case of emergency; prepare a way out of a difficult position; provide for a retreat against contingencies是什么意思_leave oneself a way out; leave oneself an option; provide a passage for escape in case of emergency; prepare a way out of a difficult position; provide for a retreat against contingencies在线翻译_英语_读音_用法_例句