“心血來潮”，漢語成語，形容一時衝動，忽然起了某個念頭。可以翻譯爲"be prompted by a sudden impulse; be seized by a whim"。常用表達如“心血來潮想做某事（feel a sudden urge to do something）”。
例句：
心血來潮改變原計劃，那怎麼行呢?
How can we change our original plan on a sudden impulse?
他突然心血來潮，想站起來唱歌。
He had a sudden impulse to stand up and sing.