casual
单词辨析：
指没有任何担忧或烦恼之事的。
My mother lives a carefree life in the country.
我的母亲在乡村过着无忧无虑的生活。
He is a carefree old man.
他是个了无牵挂的老人。
Robert remembered the carefree summers at the beach.
罗伯特记起了在海滩上度过的无忧无虑的夏日时光。
指轻松随意、无忧无虑，不把任何事放在心上的。
He takes a casual attitude towards everything.
他对待什么事情都随随便便。
They spent a casual holiday at home.
他们在家度过了一个轻松的假期。
Lucy took a casual glance at the newspaper.
露西漫不经心地瞥了一眼报纸。
指无计划或目的地选择或发生的。
a random sample of 100 families
随机抽样的100个家庭
The survey was conducted based on a random selection of women who were in the shop.
在店内随机选择了一些女性进行了调查。
指计划外或无意间发生的。
In fact, their meeting was not accidental.
事实上，他们的相遇并不是偶然的。
The company lost its advantages due to an accidental leak of its designs.
由于设计方案意外泄漏，该公司失去了优势。
指随意、并无计划的，只作定语。
She first heard of his name in a casual conversation.
她在一次偶然的谈话中第一次听到他的名字。
The professor made some casual remarks about his paper.
教授对他的论文随口点评了几句。
相关例句：
A casual observer would have taken them to be three men out for an evening stroll
乍一看的话，还以为他们三人是晚上出来散步的。
Their attempts to be casual have so far just looked arch or patronising.
他们本想做出漫不经心的样子，结果反而显得傲慢自大或自视甚高。
Even a casual observer could hardly have failed to notice the heightening of an already tense atmosphere.
即便是不经意的旁观者也一定已经觉察到本就紧张的气氛进一步加剧了。
It's difficult for me to be casual about anything
要我轻松处事很难。
She had a purposeful air, and it became evident that this was not a casual visit.
她一副无事不登三宝殿的神情，很明显，这不是一次随意造访。
Casual shoes need to wear well
休闲鞋得耐穿。