行踪无定xíng zōng wú dìng

one’s whereabouts is unknown
❍ 他一生漂泊，～。He was wandering about aimlessly all his life,and few people knew his whereabouts.

行踪无定xínɡ zōnɡ wú dìnɡ

行动的踪迹不固定。形容没有固定的住所，在各处来往出没。