absent-minded
单词辨析：
指在做某事时精力不集中的，因而造成错误、损失等。
A careless driver is a killer.
一个粗心大意的司机就是一个杀手。
He is careless about his work.
他对工作很马虎。
指某人经常丢三落四的，也许因为精力不集中，也许是由健忘症引起的。
The absent-minded professor is always losing his books.
这位健忘的教授老是丢书。
She had an absent-minded look on her face.
她脸上露出心不在焉的神色。
指对某事掉以轻心，或茫然地陷入沉思且未注意到周围的情况或活动的，通常作表语，常后接介词 of。
He rode on, heedless of danger.
他不理会危险，继续骑马前行。
She is heedless of the noises outside the window.
她没有注意到窗外的嘈杂声。
指行事鲁莽、不计后果的，作表语时常可与 heedless 换用。
a reckless teenager
一位毛手毛脚的少年
be reckless of consequences
不顾后果
He is a reckless driver.
他是个鲁莽的司机。
He is reckless/heedless of danger.
他不顾危险。
相关例句：
The absent-minded professor forgot to get off at Newcastle and was taken on to Edinburgh.
心不在焉的教授忘了在纽卡斯尔下车，一直被拉到了爱丁堡。
Do you think that an absent-minded fellow like Tom can become a master carpenter?
你认为像汤姆这样一个心不在焉的家伙能成为一名手艺高明的木匠吗？
Her mother is scatty and absent-minded.
她母亲糊里糊涂，丢三落四。
Her mind is elsewhere.; She is absent-minded.
她心不在焉。
The Absent-minded Professor: Heavens! Someone stole my wallet!
心不在焉的教授：天啊！有人偷了我的钱包！
He seemed absent-minded and as a result of his careless playing, we lost the game.
他似乎心不在焉，正因为他不用心，我们输掉了那场比赛。