形容詞 careless:

1. marked by lack of attention or consideration or forethought or thoroughness; not careful
2. effortless and unstudied
3. (usually followed by `of') without due thought or consideration
   同義詞：regardless

1. Careless driving kills!
   開車大意危及生命！
2. The security of the whole operation has been jeopardized by one careless person.
   整個(gè)作業(yè)的安全讓一個(gè)粗心大意的人給破壞了。
3. It was most careless of me.
   我真是非常粗心。
4. You're so careless.
   你真粗心。
5. Characterized by careless ease or informality; casual.
   漫不經(jīng)心的以漫不經(jīng)心或隨便態(tài)度為特點(diǎn)的; 漠不關(guān)心的
6. The careless waiter dropped the dish onto the ground.
   那個(gè)粗心的侍者把盤子摔到了地上。
7. It was careless of you to leave the door unlocked.
   你沒鎖門，太粗心了。
8. He is careless about his appearance.
   他不講究外表。

care.less

adj.（形容詞）
Taking insufficient care; negligent:
粗心的，疏忽的：不夠當(dāng)心的；忽視的：
例句：
a careless housekeeper; careless proofreading.
粗心的女管家；馬馬虎虎的校對

Marked by or resulting from lack of forethought or thoroughness:
輕率的：事先缺乏考慮的、不夠細(xì)致周密的，由于事先缺乏考慮或不夠細(xì)致周引起的：
例句：
a careless mistake.
粗枝大葉的錯(cuò)誤

Showing a lack of consideration:
草率的，欠考慮的：
例句：
a careless remark.
草率的評論

Unconcerned or indifferent; heedless:
淡漠的：不關(guān)心的或冷淡的；不加注意的：
例句：
careless of the consequences.
不顧后果

Unstudied or effortless:
隨便的：自然的或不費(fèi)勁的：
例句：
danced with careless grace.
以毫不矯揉的優(yōu)雅舞姿跳舞

Exhibiting a disposition that is free from cares; cheerful:
無憂無慮的：表現(xiàn)出輕松愉快的性情的；快活的：
例句：
a careless grin; a careless wave of the hand.
快活地咧著嘴笑；愉快的一揮手

【引伸】
care.lessly
adv.（副詞）
care.lessness
n.（名詞）
<參考詞匯><同義詞>careless,heedless,thoughtless,inadvertentThese adjectives apply to what is marked by insufficient care or attention.
這些形容詞都表示不夠小心謹(jǐn)慎的或不夠注意的。
Careless often implies negligence:
Careless 經(jīng)常含有疏忽的意思：
例句：
.It is natural for careless writers to run into faults they never think of. (George Berkeley).
.疏忽的作者會陷入他們從來沒想到過的錯(cuò)誤，這一點(diǎn)是很自然的. （喬治·貝克萊）。

Heedless suggests often reckless inattentiveness:
Heedless 常含有不顧后果的漫不經(jīng)心的意思：
例句：
.We have always known that heedless self-interest was bad morals; we know now that it is bad economics. (Franklin D. Roosevelt).
.我們已經(jīng)懂得，只顧草率地考慮自身利益在過去是道德敗壞；我們現(xiàn)在知道它代表不利的經(jīng)濟(jì)情況. （富蘭克林D·羅斯福）。

Thoughtless applies to actions taken without due thought or consideration:
Thoughtless 指沒經(jīng)過充分的思考或考慮而采取的行動(dòng)：
例句：
.At length I recollected the thoughtless saying of a great princess, who, on being informed that the country people had no bread, replied, ‘Let them eat cake’. (Jean Jacques Rousseau).
.終于，我回憶起一位偉大的王后發(fā)表的輕率議論，她在被告知鄉(xiāng)下人沒有面包吃時(shí)回答說，‘讓他們吃蛋糕吧’. （讓·雅克·盧梭）。

Inadvertent is used of actions marked by unintentional lack of care:
Inadvertent 用于指不謹(jǐn)慎的行為，而這不謹(jǐn)慎是無心的：
例句：
With an inadvertent gesture she swept the vase off the table onto the floor.
她無意地做了個(gè)手勢，把桌上的花瓶打翻到地上。