[màn bù jīng xīn]
（心不在焉地）absent-minded, a causal air, lack of attention
He replied with a casual air.
他漫不经心地回答。
Through his lack of attention to the game he had put his white stone into a “tiger's mouth” formed by three black stones.
由于他漫不经心地下棋， 他的白子掷到黑子的虎口里去了。
（不留心）pay no heed to ...
（欠缺注意力）wanting in care
（粗心的）in a careless way,careless
（疏忽的）Inadvertent
（举止轻描淡写）with a quiet easiness of bearing