漫不经心

漫不经心 [màn bù jīng xīn]

1. ■ pay no heed to ...; totally unconcerned [inattentive]; wanting in care; in a careless way; inadvertent; with a quiet easiness of bearing; absent-minded; with indifference [nonchalance]; careless; casual; negligent:

他漫不经心地回答。 He replied with a casual air.

由于他漫不经心地下棋， 他的白子掷到黑子的虎口里去了。 Through his lack of attention to the game he had put his white stone into a “tiger's mouth” formed by three black stones.