兔起鹘落

tùqǐ-húluò

[quick flow of writer's thoughts and imagination; as the moment a hare is flushed out the falcon swoops down] 兔一起动, 鹘就扑落下来。 比喻动作迅速。 亦比喻作画、 书法、 作文等下笔快、 无停顿