occur vi. (-rr-) 1.(事件等)发生。 2.被想到,想起。 3.出来,出现;存在;被发现。 An accident occurred. 发生了一起事故。 if anything should occur 如果发生什么事的话。 A happy idea occurred to me. 我想起了一个好办法。 It occurred to me that ....我想到…。
happen vi. 1.发生,〔口语〕出现。 2.〔后接不定式〕偶然…,碰巧… (to do)。 Do you happen to remember his name 你还记得他的名字吗? If anything should happen to me ... 万一我有不幸…。 It (so) happened that... 偶然,…碰巧。 No matter what [whatever] happens 不管发生什么事,不管出现甚么情况。 as it happens 碰巧 (As it happens, I have left the book at home. 偏巧我把书放在家里了)。 be likely to happen 可能要发生。 happen in 〔美国〕偶然到…(来)。 happen in with 偶然和…碰见。 happen on [upon] 偶然看到[碰到、想到]。 happen what may 无论发生甚么事,不管怎样。