1 (formal 正式) to happen, especially in a way that has not been planned 发生(尤指偶然地):
The accident occurred late last night.那宗意外于昨天深夜发生。☞Look at the note at happen. 参看happen的注释。
2 to exist or be found somewhere 存在;找得到:
The virus occurs more frequently in children.这种病毒更经常存在于儿童身上。
3occur to sb (used about an idea or a thought) to come into your mind (指主意、想法)(指某人)想起,想到:
It never occurred to John that his wife might be unhappy.约翰从没有想到他的妻子可能会不快活。