偶然的的英文：
accidental
adventitious
aleatory
casual
causeless
fortuitous
haphazard
incidental
involuntary
occasional
stray
unpremeditated

参考例句：

Happening by chance or accident;fortuitous.
偶然的偶然或意外发生的;偶然的

An accidental or unpredictable event.
偶然的事，意想不到的事

The occurrence of such things is by no means fortuitous.
出现这种问题绝不是偶然的。

The occurrence of such things is by no means fortuitous
出现这种问题绝不是偶然的。

He happened on the book in a secondhand bookstore
他在旧书店偶然发现了这本书。

Chance had chucked us together at a skiing resort.
偶然的机缘使我们在一个滑雪胜地相遇。

Justice is incidental to law and orde.
对于法律和秩序，公正是偶然的。

Their accidental meeting led to a renewal of their acquaintance.
偶然的相遇使他们重续前缘。

Sam struck on that anthology in a second hand book store
萨姆在一家旧书店里偶然发现了那本选集。

I found out by chance that she was actually a freshman from London University.
我偶然发现她实际上是伦敦大学的一年级学生。

accidental是什么意思：
adj. 意外的；偶然的；附属的，附带的
n. 非主要特性，非本质属性，次要方面

His rudeness was conscious, not accidental.
他的粗暴无礼是故意的，不是偶然的。

an accidental misstep threatening (or causing) a fall.
会导致摔倒的意外失足。

Even their agonies have an accidental effect of clownishness
即便是他们的极度痛苦地带有一种滑稽的意味。

adventitious是什么意思：
adj. 偶然的，外来的

adventitious fiber root
不定须根

The strike was broken, of course, but mainly by a series of adventitious developments.
罢工当然给解散了，但主要是由于出了一些意外事件。

The fall of a leaf heralds the advent of autumn
一片落叶预兆秋天的来临。

aleatory是什么意思：
a. 贪图侥幸的,偶然的

an aleatory contract between an oil prospector and a landowner.
石油勘探者和地产所有者之间的一项盈亏未定的合约