掉以輕心

To fall or drop; to lose or go missing; to shed or peel off; to swing or wag; to turn or rotate; to exchange or swap; used after verbs to indicate completion or removal.

to use; by means of; according to; in order to; because of; to consider as; to lead; to be able to; to make

Not heavy; easy; gentle; soft; to make light of; to disparage; unimportant; small in number; unstressed.

The physical heart; the mind or intellect; feelings or emotions; the center or core of something; intention or will.