I met my workmate Mark this morning. He was going to take part in the Chinese Speech Contest, so I asked with concern, "Mark, how have you prepared for the Chinese Speech Contest this afternoon?" He answered confidently, "我都准备好了！我对赢得这次比赛，胸有成竹！" Here, Mark used the idiom, "胸有成竹" (xiōnɡ yǒu chénɡ zhú). His answer means that "I have been well prepared for it! I'm sure about winning the contest!"
Chinlingo早上遇到要参加汉语演讲比赛的同事Mark，关切地问他："今天下午的汉语演讲比赛，你准备得怎么样了？"Mark满脸自信地回答："我都准备好了！我对赢得这次比赛胸有成竹！"Mark在对话中用了一个成语——"胸有成竹"（xiōnɡ yǒu chénɡ zhú）。说明Mark对汉语演讲比赛准备充分，十分有把握赢得比赛。
"胸" (xiōnɡ), an equivalence of "chest", refers to the front part of the body between the neck and the stomach in modern medicine. Ancient Chinese people used it to represent one's "心" (xīn) or "heart" in English. Moreover, "心" also refers to one's thoughts, memory, emotions and other psychological activities. "成" means "be complete", so "成竹" means "complete bamboo".
"胸有成竹" meant "a painter has the image of a complete bamboo in his mind before he paints it" originally.
It originates from the story of bamboo painting by Wen Tong, a painter in China's Northern Song Dynasty. According to the story, Wen Tong was extremely skillful in bamboo painting after years of observation and repeated practice, and his bamboo paintings were so vivid that no one could match him. Over time, the story of Wen Tong has been used to mean "be well prepared and absolutely sure about something".
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