This is the 1682nd most frequent Chinese word.
不幸
Misfortune; unhappiness.
Here, '不幸' refers to an adverse event that has impacted someone's life negatively, acting as a noun meaning 'misfortune'.
他的家庭遭遇了一场不幸。
His family encountered a misfortune.
In this sentence, '不幸' is used as an adverb meaning 'unfortunately' to accentuate the unfavorable aspect of an event.
在那次事故中，他们不幸受伤。
They unfortunately got injured in that accident.
Here, '不幸' carries the meaning of adversity or unfortunate circumstances, used as a condition emphasizing the challenging situation faced.