In the Warring States Period, the State of Qin besieged the capital of the State of Zhao. Duke Pingyuan of Zhao planned to ask the ruler of the State of Chu personally for assistance. He wanted to select a capable man to go with him. A man called Mao Sui volunteered. When the negoti-actions between the two states were stalled because the ruler of Chu hesitated to send troops, Mao Sui approached him, brandishing a sword. At that, the ruler of Chu agreed to help Zhao, against Qin.
戰(zhàn)國(guó)時(shí)代，秦國(guó)軍隊(duì)攻打趙國(guó)的都城。趙國(guó)的平原君打算親自到楚國(guó)去請(qǐng)救兵，想挑選一個(gè)精明能干的人一同前去。有一個(gè)名叫毛遂的人，自告奮勇愿意同去。平原君到楚國(guó)后，與楚王談了半天，沒(méi)有一點(diǎn)結(jié)果。毛遂怒氣沖沖地拿著寶劍，逼近楚王，終于迫使楚王答應(yīng)出兵，與趙國(guó)聯(lián)合共同抵抗秦國(guó)。

This idiom means to recommend oneself.
“毛遂自薦”這個(gè)成語(yǔ)用來(lái)比喻自己推薦自己，不必別人介紹。

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