Historical Record Volume 76 Prince Ping Yuan Biographies：
《史记》卷七十六《平原君虞卿列传》记载：
Qin's troops laid siege to Handan, the capital of the State of Zhao.
春秋时，秦军在长平一线，大胜赵军。秦军主将白起，领兵乘胜追击，包围了赵国都城邯郸。
Therefore, Prince Ping Yuan was to be sent on a mission to the State of Chu to form an alliance against Qin.
大敌当前，赵国形势万分危急。平原君奉赵王之命，去楚国求兵解围。
Among the guests fed by Ping Yuan was a man called Mao Sui who went up to his host and recommended himself as a member of the Prince’s suite.
平原君把门客召集起来，想挑选20个文武全才一起去。他挑了又挑，选了又选，最后还缺一个人。这时，门客毛遂自我推荐，说:“我算一个吧！”
The negotiations between the Prince and the King of Chu proceeded without substantial results.
到了楚国，楚王只接见平原君一个人。两人坐在殿上，从早晨谈到中午，还没有结果。
Seeing this, Mao Sui mounted bravely the platform where the negotiations were being held and stated the advantages and disadvantages.
毛遂大步跨上台阶，把出兵援赵有利楚国的道理，作了非常精辟的分析。
The King of Chu was at last convinced and decided to dispatch his troops for saving the State of Zhao.
毛遂的一番话，说得楚王心悦诚服，答应马上出兵。
Now, this allusion is used to refer to those who volunteer to offer one's services for a task or a job.
成语“毛遂自荐”由此而来， 比喻不经别人介绍，自我推荐担任某一项工作。
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