心血来潮

心血来潮 [xīn xuè lái cháo]

1. ■ take it into one's head; (have) a sudden inspiration; A sudden thought hit one.; be seized with a sudden impulse; be prompted by a sudden impulse; be seized by a whim; suddenly think of a thing:

心血来潮忘乎所以 be carried away by one's whims and act recklessly;

一时心血来潮， 就改变了原计划， 那怎么行呢? How can we change our original plan on a sudden impluse?