• vi. 發生；碰巧；偶然遇到

hap,發生，運氣，機會，詞源同happy.即好運發生，后用于中性詞即可指發生的好運也可指壞運。

happen

happen: [14] Surprisingly for such a common verb, happen is a comparatively recent addition to the English language. Old English had a number of verbs denoting ‘occurrence’, all long since defunct, including gelimpan and gescēon, and in the 13th century befall began to be used for ‘happen’, but the first signs we see of the coming of happen are when English acquired the noun hap ‘chance, luck’ in the 13th century.

It was borrowed from Old Norse happ, a word of uncertain ancestry but probably related to Old Slavic kobu ‘fate’ and Old Irish cob ‘victory’, and represented in Old English by geh?p ‘fit’. In the 14th century it began to be used as a verb meaning ‘happen by chance’, and hence simply ‘happen’, and before the century was very old it had been extended with the verbal suffix -en to happen.
=> happy, perhaps

happen (v.)

late 14c., happenen, "to come to pass, occur, come about, be the case," literally "occur by hap, have the (good or bad) fortune (to do, be, etc.);" extension (with verb-formative -n) of the more common hap (v.). Old English used gelimpan, gesceon, and Middle English also had befall. In Middle English fel it hap meant "it happened." Related: Happened; happening. Phrase happens to be as an assertive way to say "is" is from 1707.

1. Remember, keep a positive attitude and good things will happen.

記住：保持樂觀的心態，好事自然會發生。

來自美劇《摩登家庭》

2. Do not wait for good things to happen to you. You need to walk towards happiness.

不要等待好事降臨，你要向幸福進發。

來自金山詞霸 每日一句

3. This is such an unforeseeable situation that anything could happen.

這種情況很難預測，什么事都有可能發生。

來自柯林斯例句

4. I go all tingly when I think of what might happen.

我一想到可能發生的事就滿心歡喜。

來自柯林斯例句

5. He couldn't help worrying obsessively about what would happen.

他禁不住時刻擔心將會發生的事情。

來自柯林斯例句