晉代的祖逖是個胸懷坦蕩、具有遠大抱負的人。可他小時候卻是個不愛讀書的淘氣孩子。進入青年時代，他意識到自己知識的貧乏，深感不讀書無以報效國家，于是就發奮讀起書來。他廣泛閱讀書籍，認真學習歷史，于是就發奮讀起書來。他廣泛閱讀書籍，認真學習歷史，從中汲取了豐富的知識，學問大有長進。他曾幾次進出京都洛陽，接觸過他的人都說，祖逖是個能輔佐帝王治理國家的人才。祖逖24歲的時候，曾有人推薦他去做官司，他沒有答應，仍然不懈地努力讀書。

　　后來，祖逖和幼時的好友劉琨一志擔任司州主簿。他與劉琨感情深厚，不僅常常同床而臥，同被而眠，而且還有著共同的遠大理想：建功立業，復興晉國，成為國家的棟梁之才。

　　一次，半夜里祖逖在睡夢中聽到公雞的鳴叫聲，他一腳把劉琨踢醒，對他說：“別人都認為半夜聽見雞叫不吉利，我偏不這樣想，咱們干脆以后聽見雞叫就起床練劍如何？”劉琨欣然同意。于是他們每天雞叫后就起床練劍，劍光飛舞，劍聲鏗鏘。春去冬來，寒來暑往，從不間斷。功夫不負有心人，經過長期的刻苦學習和訓練，他們終于成為能文能武的全才，既能寫得一手好文章，又能帶兵打勝仗。祖逖被封為鎮西將軍，實現了他報效國家的愿望；劉琨做了都督，兼管并、冀、幽三州的軍事，也充分發揮了他的文才武略。

　　故事出自《晉書·祖逖傳》。成語“聞雞起舞”，形容發奮有為，也比喻有志之士，及時振作。

rising up upon hearing the crow of a rooster to practise sword playing

  zu ti of the jin dynasty（265-420）was a big-hearted and farsighted person who,however,was very naughty and did not like to study when he was a small kid.when he became a young man,he felt acutely that his knowledge was inadequate and that he could not serve his country well if he did not study hard.so he put all his energies into his study.he read extensively,seriously studied history from which he absorbed rich knowledge,and made good progresss in his studies.he had been to the capital city luoyang several times,and all the people who had to the capital city luoyang several times,and all the people who had come into contact with him said that zu ti was a talented person who was capable of assisting the emperor in governing the country.when he was 24,someone recommended hem to be an official,but he refused the post.he was still making a sustained effort in his studies.later,both zu ti and liu kun,his close frined since early childhood,were appointed chief clerks responsible for document administration in the sizhou prefecture.he and liu kun cherished a deep affection for each other.they not only often shared the same bed in sleeping,but also shared the same lofty ideals;to render meritorious service in rejuvenating the jin dynasty and play the part of the pillars of the state.once,zu ti heard a cock crow in the wasteland in his dream at midnight.he kicked liu kun a wake,saying to him:"people say it is inaupicious to hear a cock crow in the wasteland.i don's think so.what about getting up and practicing sword playing the moment we hear the cock crow form now on?"liu kun agreed readily.so every day when the cock crow,they got up and practied sword playing,the cold steel of the swords glinting and flashing.day by day and year in,year out,they never stopped.as the saying goes,constant effort yields sure success.through long periods of hard study and training,they finally becaome versatile persons versed in both civil and military affairs.they could write good essays,and were capable of leading troops in fighting victoriously.zu ti was invested with the title the general for guarding the western regions,thus realizing his wish of rendering meritorious service to the country.liu kun became a governor,and at same time was in charge of the military affairs of the three prefectures of bingzhou,jizhou and youzhou.in discharging his duties,liu kun also fully displayed his talent in both polite letters and martial arts.this stroy appears in "the life of zu ti" in the history of the jin dynasty.from this story people have coined the set phrase" rising up upon hearing the crow of a rooster to practise sword playing' to signify that someone is exerting himself to do something worthwhile.it is also used to signify that a person of noble aspirations exerts himeself in time.