/ˈhæpən ||; ˈhæpən/verb[I] 1 (of an event or situation) to take place, usually without being planned first （指事情或情况）发生: Can you describe to the police what happened after you left the party? 你离开舞会后发生了什么事情，可以对警方描述一下吗？How did the accident happen? 这起事故是怎样发生的？
Happen and occur are usually used with events that are not planned. Occur is more formal than happen. Take place suggests that an event is planned The wedding took place on Saturday June 13th. happen和occur通常用于未经计划的事件。与happen相比，occur多用于正式场合。按计划发生的事件用take place：The wedding took place on Saturday June 13th. 婚礼在6月13日星期六举行。 2 happen to sb/sth to be what sb/sth experiences （某人或某物）发生（某情况）: What do you think has happened to Julie? She should have been here an hour ago. 你看朱莉出了什么事？她一小时前就该到了。What will happen to the business when your father retires? 你爸爸退休后，这生意会怎么样？
3 happen to do sth to do sth by chance 偶然；碰巧: I happened to meet him in London yesterday. 我昨天在伦敦碰巧遇上他。
as it happens/happened (used when you are adding to what you have said) actually （用于补充说过的话）真的:
As it happens, I did remember to bring the book you wanted. 你要的那本书我真的记得给你捎过来了。 it (just) so happens→
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