Look at someone with new eyes/knock the socks off someone
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Lv Meng (lǚ m?ng 呂蒙) was a general of Wu during the Three Kingdoms Period (三國時代,220-280AD).
三國時期(220-280)，吳國有壹個叫呂蒙的將軍
He was born in such a poor family that he did not get any chance to go to the school when he was a child.
呂蒙出生在窮苦人家，小時候沒有機會上學。
However, there was still less time for reading when he served in the army after he grew up.
長大後他參了軍，看書的時間更少了。
Once the king of Wu summoned Lv Meng and said to him, "Since you are now a general in power, you had better read some books to widen your horizon."
壹次，吳國的皇帝召見呂蒙，對他說："現在妳是大將軍了，應該多看看書開闊眼界。"
Lv Meng answered, "I am so busy with military affairs that I am afraid I have little time to read."
呂蒙回答道："軍中的事務這麽忙，我恐怕沒有時間讀書。"
The King said, "Are you busier than I am? Even I often find time to read books on the art of war and gain much benefit from them. To read more about the experience left by our ancestors will make you progress."
吳國的皇帝說："妳難道比我還忙嗎?我常常抽空閱讀兵書，從中得到了不少好處。多看看前人的經驗之談，妳會有更大的進步。"
Lv Meng then did according to what the king said. He concentrated himself on reading history and military writings.
呂蒙接受了皇帝的建議，從此開始專心閱讀，看了很多歷史和軍事書籍。
On day, Military Governor Lu Su visited Lv Meng and was surprised to find that Lv Meng had become very knowledgeable.
壹天，主帥魯肅來拜訪呂蒙，驚訝地發現呂蒙變得很有學問。
Lu Su, who held Lv Meng in contempt earlier, said, "I did not expect that you would know so much besides fighting! You are not the one you used to be!"
曾經非常輕視呂蒙的魯肅說："我以為妳只會打仗，沒想到妳這麽博學。妳已經不是過去的那個呂蒙了!"
Lv Meng replied, "You should look at a person with new eyes even only after a three days' separation."
呂蒙回答道："即使妳和別人只分開了三天，三天後再遇到他時也不能用三天前的老眼光來看待他。"