士别三日,当刮目相待
Contents
Who do not three days, when Guamuxiangdai
  Explanation: An improvement that others can not see him with her old eyes.
  Source: "Three Kingdoms Wu Lu Meng Biography" note cited "Jiang Table Biography" who do not three days, which is more Guamuxiangdai. "
  Examples: (Cai) is always ~ for Lu Xun's. (Guo, "Lu Xun and Wang Guowei")
No. 2
  士别三日,当刮目相待 (shì bié sān rì,dāng guā mù xiāng dài)
  【解释】:指人在短时间内有极大的进步,要改变对他的看法。
  【出处】:《资治通鉴》卷六十。孙权劝学 司马光
  【示例】:(蔡元培)对于鲁迅始终是~的。 ★郭沫若《鲁迅与王国维》
  【故事】:三国时期,东吴能武不能文的武将吕蒙听了孙权的劝告后,发奋读书。一段时间后,都督鲁肃来视察吕蒙的防地。吕蒙就对蜀防备的事情讲得有条有理,还写份建议书给鲁肃,鲁肃很惊讶。吕蒙说道:“士别三日,就要刮目相看。”