I wouldn't knowused to say that you do not know the answer to something and that you are not the person who would know 我可不知道,我可不清楚〔表示你不知道某事的答案,而且也不是应该知道此事的人〕I wouldn’t know• "When's he coming back?" "I wouldn't know."
→ I wouldn’t know at know1(SPOKEN SECT)