出自南北朝无名氏的《木兰诗》，兔子被提起双耳悬空时，雄兔四脚乱动，雌兔双眼半闭的情形。形容事物错综复杂，不易弄清真相。
From the anonymous poem “The Song of Mulan” from the Northern and Southern Dynasties period. It describes a rabbit dangling by its ears – the buck wildly kicking its legs, the doe with half-closed eyes. It refers to a situation so complicated and convoluted that the truth is difficult to discern.
在古代，有个叫花木兰的姑娘。她见到征发父亲参军打仗的文书后，每天不停地叹息。她的父亲年轻时曾为朝廷效过力，后来因为年纪大了，才得以从前线返回。如今朝廷又要征发父亲去前线打仗，他老人家那样的年龄怎能经受得住这般劳累？况且，她的弟弟还很小，让他去前线打仗也不现实。
In ancient times, there was a young woman named Mulan. When her elderly father was conscripted into the army again, despite having served the court in his youth, Mulan sighed in distress daily. Her little brother was too young for the harrowing battlefield.
木兰考虑再三，最后决定自己女扮男装，替父亲从军。她把这个想法讲给父母听，父母听后极力反对，但不这样做也没有更好的办法，他们也只得同意了。
After much thought, Mulan decided to disguise herself as a man and serve in her father’s stead. Though her parents vehemently objected at first, they had no better option and relented.
征期很快就到了，花木兰辞别父母，随大军赶到边关。她虽是个女儿身，但有一身好武艺，就是普通男子也比不上她。她在战场上表现得很勇敢，立过很多战功，经过十年的艰苦征战，他们终于打败强敌，凯旋回朝。
Soon the recruitment date arrived. Bidding her parents farewell, Mulan rushed to the frontier with the army. Though a woman, her martial skills surpassed ordinary men’s. She fought valiantly, compiling distinguished military feats over a grueling decade until finally vanquishing the enemy forces triumphantly.
皇帝论功行赏，把花木兰封为尚书郎。花木兰本无意于功名，又担心女扮男装的事情泄露，就以孝敬父母为名推辞。皇帝见她如此孝顺，就成全了她。
To honor her service, the Emperor designated Mulan as a high-ranking scholar-official. However, concerned her crossdressing might be exposed, Mulan declined under the pretext of dutifully returning home to her parents. Impressed by such filiality, the Emperor indulged her wish.
花木兰回到家后，重新穿上女人的衣服，梳妆打扮一番后，出来见众人。她的战友们看到她这个样子，都吃惊地感叹到：“和你在一起十二年，竟然不知道你是个女儿家！”
Upon returning home, Mulan resumed women’s clothing and styled herself properly before revealing her identity. Her comrades gasped in astonishment: “We fought alongside you for twelve years without realizing you were actually a woman!”
后来有人因此事而写了一首《木兰诗》，诗中有这样几句话：“雄兔脚扑朔，雌兔眼迷离，双兔傍地走，安能辨我是雄雌？”意思是说，提着兔子的耳朵悬在半空时，雄兔两只前脚时时动弹，雌兔两只眼睛时常眯着，所以容易辨认。如果两只兔子贴着地面并排跑，谁能分辨出哪一个是雄兔、哪个是雌兔呢？
Later, this tale inspired “The Song of Mulan” containing the lines: “The buck kicks its legs chaotically, the doe’s eyes dazed and muddled; the rabbits race alongside – yet who can discern the males from females?” When dangling by the ears, the sexes are distinct; but when running together on the ground, male and female appear indistinguishable.