Thank Kin for correcting :)
Chinese Idiom Stories 4: Outwardly Strong Inwardly Weak(外强中干)
A long long ago, the States of Qin and Jin had a went to war. The King of Jin wanted to use horses that the State of Zheng gave him as a present presented. There was the secretary of Jin named called Zheng Qing（庆郑）who told advised to his king, "From ancient times to the present Until now, we should must use our own good horses for wars because they are natives. These (Our) horses are familiar with (know) the roads and listen to us understand our commands. And foreign horses are not easy to master, once an accident happens, they would be kicked and screamed get scared and run around crazily(wildly). Besides, those horse look like outwardly strong but they are inwardly weak (on the inside) in fact. How could they fight?" But the king didn't adopt his suggestion.
After the war began, the chariots and horsemen of the State Jin were out of control and soon became chaos the chaos started. FinallyIn the end, the army of Jin was completely destroyed defeated totally by (the state of)Qin, and the King of Jin also was also captured.
Then sentence "outwardly strong inwardly weak(Strong in the outside, but weak on the inside) (外强中干)" that Zheng Qin said became an idiom since then. "外" means appearance, "中" means inside, "干" refers to empty and weak , "强" is strong and powerful. It is used to describe something that has a strong appearance but internal force actually empty an empty interior.
In addition, there is another idiom that is similar to it, 色厉内荏. "色" means look or expression, "厉" is fierce and tough, "荏" is weak. So this idiom is uesed to describe calls those who is are tough in appearance but inner fear coward on the inside.
Below is the original:
秦国和晋国之间发生了战争，晋惠公要使用郑国赠送的马来驾车。大臣庆郑劝告惠公说：“自古以来，打仗时都要用本国的好马，因为它土生土长，熟悉道路，听从使唤。用外国的马，不好驾驭（控制），一遇到意外，就会乱踢乱叫。而且这种马外表看起来好像很强壮，实际上并没有什么能耐（原文是‘外强中干’），怎么能作战呢？”但是惠公没有听从庆郑的劝说。
战斗打响后，晋国的车马便乱跑一气，很快陷入泥泞，进退不得。结果被秦军打得大败，晋惠公也被秦军活捉了。
庆郑所说的“外强中干”这句话，后来就成了成语。“外”是外表，表面；“中”是中间，内部；“干”是干枯、空虚。用来形容外表强大、实际上内部力量空虚。
和这近似的成语有“色厉内荏”。“色”是脸上的神色；“厉”是凶猛；“荏”是软弱。这句成语是说外表强硬而内心胆怯。
If you like this story, please help me to correct it, thank you very much. (^.^)
