(1) 1)偶然发生((of an event，accident，etc)take place，occur often by chance)[I]：What～ed?发生了什么事?What time/How/When did the accident～?事故是什么时间/怎样/何时发生的?〖同〗occur; 2)经历，降临到……头上(the result of an event or course of action)[I+prep (to)]：If anything/nothing～s to sb... 如果某人出了什么事/没出意外……;A strange thing/bad accident～ed to him.他发生了一件奇怪的事/严重的事故。What～ed to my car/salary?我的车子/工资怎么啦?

(2)碰巧，偶然 (have the fortune or lot (to do or be as specified))[I+to-inf]：I～ed to know about him.我恰好知道他。 It～ed that the weather was bad/he had no money with him.碰巧天气不好/他身上没带钱。

(3)巧遇，偶然发现(找到)(find sth/sb by chance)[I+prep (on/upon)](fml)：He～ed on/upon the answer/perfect solution to the main problem/a clue to the mystery.他偶然找到了答案/那个主要问题完美的解决办法/解这个谜的线索。～on sb in India/a band of gipsies 在印度巧遇某人/偶遇一群吉普赛人;

as it happens/happened 碰巧，偶然：As it～s，I had my cheque book stolen that day. 那天我的支票簿正好被盗。

→′happening n(常pl)发生的事，事件;引人注目的事件;即兴表演;

【辨异】happen与chance、occur和take place 的区别见CHANCE。