音标：英 /əˈkɜːd/，美 /əˈkɜːrd/
词性：动词（occur 的过去式和过去分词）；形容词（表示“发生的”）
表示事件、情况或想法在特定时间或地点“发生”“出现”，多用于正式语境，常需明确时间或地点状语。
描述具体事件发生
后接时间/地点状语，强调明确的时空背景。
例：The accident occurred in Riverside, California.（事故发生在加利福尼亚州的河边市）
例：A violent earthquake occurred there.（那里发生了强烈地震）
表示“突然想到”
用于固定句型 It occurred to sb. that...，指想法或灵感突然出现。
例：The idea occurred to him in a dream.（这个主意是他在梦中想到的）
例：It occurred to him that he had left his keys at home.（他突然想起钥匙落在家里了）
常见搭配
occur as：以……形式出现（例：Mistakes occurred as errors in data entry.）
occur during/at：在……期间/时刻发生（例：The break-in occurred just before midnight.）
unexpectedly/rarely occurred：意外/罕见发生（例：Something unexpected occurred.）
The collision occurred in the busiest shipping lanes in the world.（撞船事故发生在全世界最繁忙的航道上）
Teamwork improves with time: 73% of incidents occurred on a crew's first day of flying together.（团队协作随时间提升：73%的事故发生在机组首次合作飞行当天）
Similar incidents have occurred before.（类似事件以前也发生过）
You were going to an interview when the incident occurred, right?（事情发生时你正要去面试，对吧？）
The department denies responsibility for what occurred.（该部门拒绝为所发生的事承担责任）
Overproduction caused economic tremors that occurred last year.（生产过剩引发了去年的经济波动）
The shooting occurred in the 34th Precinct.（枪击事件发生在第34警区）
Glaciation occurred toward the end of the Permian period.（冰川作用发生在二叠纪末期）
Hundreds were killed, and thousands made homeless after the conflict occurred.（冲突发生后，数百人死亡，数千人流离失所）
It occurred to her that she had forgotten the meeting.（她突然想起忘了开会）
occurred vs. happened：前者更正式，强调具体时空或逻辑关联；后者为通用词，口语中更常见。
例：The accident occurred at 3 p.m.（强调时间） vs. What happened next?（无明确时空）
理解 occurred 的关键在于把握其“正式性”和“时空关联性”，无论是描述客观事件还是主观灵感，均需清晰传递“何时何地发生”的核心信息。在写作或正式表达中，它比 happened 更能体现语言的精准性。