To have an image of bamboo in one's mind

　　Wang Xi-zhi is one of the most famous calligraphers during the Eastern Jin Dynasty of China. When he was very young, he practiced his art every day and never stopped.

　　Later he absorbed the strong points of all the other schools of calligraphy1, and developed his own unique style of writing. Because of his achievements, he has been honored as one of China's sages2 of calligraphy.One time, Wang Xi-zhi sketched3 in wood for an engraver4 to cut. Then the engraver found the ink had penetrated5 one centimeter into the wood.

　　"Ru Mu San Fen6" is got from this story, which means the calligraphy is penetrating7.

　　Now it is often used to describe expressing sharp ideas or profound views.

　　　　入木三分

　　王羲之是中國東晉時(shí)代一個(gè)很有名的書法家，他從小就刻苦練字，從不間斷，以后又吸取了各個(gè)不同書法派的優(yōu)點(diǎn)，形成他自己獨(dú)特的個(gè)性。因?yàn)樗跁ㄉ系某删?，人們都尊稱他為中國書法界的“圣人”。

　　有一次，王羲之在木板上刻字，后來刻字的人發(fā)現(xiàn)墨汁滲入木板有三尺深。

　　“入木三分”就是從這個(gè)故事中得出來的，用來形容書法有力，現(xiàn)在多用來比喻分析問題很深刻。