day and night

　　没日没夜；日日夜夜；夜以继日

　　This phrase means that someone has been working hard or studying hard all the time。

　　这个短语形容某人一直抓紧时间地辛勤工作或学习。

　　To finish the task on time， we have worked day and night。

　　为了能按时完成任务，我们这几天没日没夜地工作。

　　His job requirement is to be on call day and night。

　　他的工作要求随时待命。