意外 + Verb
The word 意外 (yìwài) can function as a verb or adverb meaning 'unexpectedly' or as a noun meaning 'accident.' It describes events that occur without warning or outside of expectations. For example, 意外广播 means 'accidentally broadcast.'
他意外地在旧书店里遇到了老同学。
Tā yìwài de zài jiù shūdiàn lǐ yùdào le lǎo tóngxué.
He unexpectedly ran into an old classmate at the used bookstore.
这次意外让他住了三天医院。
Zhè cì yìwài ràng tā zhù le sān tiān yīyuàn.
This accident put him in the hospital for three days.
我们意外发现这家小店的咖啡特别好喝。
Wǒmen yìwài fāxiàn zhè jiā xiǎo diàn de kāfēi tèbié hǎo hē.
We unexpectedly discovered that this little shop's coffee is especially good.