occur [əˈkɜːr]
v.发生;出现;存在于;出现在
第三人称单数： occurs现在分词： occurring过去式： occurred过去分词： occurred
1. 表示“发生”“出现”，是不及物动词，所以不能带宾语，不用于被动语态。如：
When exactly did the incident occur?
这一事件究竟是什么时候发生的？
exactly [ɪɡˈzæktli]
adv.精确地;准确地;确切地;(要求得到更多信息)究竟，到底;(答语，表示赞同或强调正确)一点不错，正是如此，完全正确
Sugar occurs naturally in fruit.
水果天然含糖分。
naturally [ˈnætʃrəli]
adv.顺理成章地;自然地;当然地;天然地;自然而然地;合理地;理所当然地
The crash occurred when the crew shut down the wrong engine
机务人员关错了引擎，随即飞机坠毁。
crash [kræʃ]
n.撞车;碰撞;相撞;(倒下、破碎等突然的)碰撞声，破裂声，碎裂声;暴跌;倒闭;破产;失败
v.碰撞;撞击;(使)猛撞;使发出巨响
adj.应急的;速成的
engine [ˈendʒɪn]
n.发动机;引擎;火车头;机车;有…型发动机的;有…个引擎的
vt.给…安装发动机
The same idea had occurred to Elizabeth.
伊丽莎白也想到了这个主意。
The time when a solar eclipse will occur can be calculated.
日食发生的时间可以推算出来。
see a lunar eclipse; 看到月食
There will be an eclipse of the moon next month.
下个月有月食。
solar [ˈsoʊlər]
adj.太阳的;太阳能的
eclipse [ɪˈklɪps]
n.日食;月食;(重要性、权势等的)丧失，黯然失色，暗淡
v.遮住…的光;使失色;使相形见绌;使丧失重要性
an eclipse of the sun/moon
日食；月食
a total/partial eclipse
全食；偏食
A total solar eclipse is due to take place some time tomorrow.
明天某个时刻会发生日全食。
Her work was in eclipse for most of the 20th century.
她的作品在20世纪大部分时间里都湮没无闻。
Her eyes were in eclipse.
她的眼睛黯淡无光。
Curiously, the word ‘gay‘ does not occur in the index
奇怪的是，gay这个词没有出现在索引当中。
Food shortages often occur in time of war.
在战争期间常常发生粮食短缺的情形。
Although it is predominantly a teenage problem, acne can occur in early childhood
虽然粉刺多发于青少年时期，但也可能在刚进入童年时期就出现。
predominantly [prɪˈdɑːmɪnəntli]
adv.主要地;多数情况下
acne [ˈækni]
n.痤疮;粉刺
Frosts often occur in November.
11月份经常出现霜冻。
There will come a time when the crisis will occur.
危机总有一天会爆发。
Changes in temperature occur slowly and are constrained
within relatively tight bounds.
温度变化缓慢，而且局限在相对较小的范围内。
constrain [kənˈstreɪn]
v.强迫;强制;迫使;限制;限定;约束
relatively [ˈrelətɪvli]
adv.相当程度上;相当地;相对地
Meat and fish are relatively expensive.
肉和鱼相对来说比较贵。
bound [baʊnd]
adj.一定会;很可能会;受(法律、义务或情况)约束(必须做某事);有义务(做某事);因…受阻(或不能正常工作)
v.跳跃着跑;形成…的边界(或界限)
n.蹦跳;跳跃
When vacancies occur, the office puts out feelers to the universities.有空缺职位的时候，办事处就到各个大学去打探。
正误辨析：
地震发生在黎明。
误：When the earthquake was occurred.
正：The earthquakeoccured at dawn.
发生了一件出乎意料的事。
误：Something unexpected was occurred.
正：Something unexpected occurred.
2. 表示某想法、观念出现在某人脑海中或被某人想到，通常与介词 to连用。常用结构：
occur to sb；it occurs to sb that;it occurs to sb to do
The same idea had occurred to Elizabeth.
伊丽莎白也想到了这个主意。
The idea occurred to him in a dream.
这个主意是他在梦中想到的。
His name just did not occur to my memory. 我就是想不起他的名字。
在以上用法中，若主语为从句或不定式，则在句首使用形式主语 it, 而把真正的主语放在后面。如：
It didn‘t occur to him that his wife was having an affair.
他没有想到自己的妻子有婚外情。
have an affair有婚外情，有外遇
It occurred to me that I could have the book sent to me
我想到可以让人把书寄给我。
It occurred to me that he might be lying. 我忽然想起他可能是在说谎。
It never occurred to me to insure the house. 我从来也没想到过去给房子投保。
insure [ɪnˈʃʊr]
v.投保;给…保险;接受投保;承保
It did not occur to me to check my insurance policy.
我没有想到要核实我的保险单条款。
insurance [ɪnˈʃʊrəns]
n.保险;保险业;保险费;保费
policy [ˈpɑːləsi]
n.政策;方针;原则;为人之道;保险单
Didn’t it occur to you to phone them about it? 难道你就没有想到给他们打个电话?
It didn‘t occur to her to ask for help.
她没想到请别人帮忙。
An idea has occurred to me.我有主意了。
Did it ever occur to you that...?你可曾想到...?
It never occurred to her to ask anyone.她从未想到问问他人。
3. 有时用于there be句式中替换动词be。如：
Not long after this, there occurred a sudden revolution. 此后不久，突然爆发了革命。
In March 1770, there occurred what became known as the Boston Massacre. 在1770年3月爆发了人们熟悉知的波士顿大屠杀。
《柯林斯高阶英汉双解学习词典》
massacre [ˈmæsəkər]
n.屠杀;残杀;(运动或比赛中的)惨败
v.屠杀;杀戮;(在运动或比赛中)使惨败
Nobody survived the massacre.
这次大屠杀无人幸免。
300 civilians are believed to have been massacred by the rebels
据信有300位平民被叛乱分子残杀。
happen、 occur、 take place同义词解析
1）.happen v. 发生
普通用词，多用于偶然事件。(尤指偶然)发生，出现;(作为结果)出现，发生;碰巧;恰好; 主语为“事”
The accident happened at 5 o‘clock.
事故发生在5点钟。
What happened then?
后来又发生了什么事？
What has happened?出什么事了?
The accident happened at 5 o‘clock.
事故发生在5点钟。
happen to do/be碰巧
She happened to be out when he called.他打电话时, 她恰巧不在家。
Has anything happened to him？ 他出什么事了吗？
She hoped nothing bad would happen to him. 她希望不会有什么不幸的事发生在他头上。
2).occur v. [比较正式]发生
可用于偶然事件或计划之事，可与 happen 换用。
The earthquake occurred/happened at dawn.
地震发生在黎明时分。
A serious traffic accident occurred/happened yesterday.
昨天发生了一起严重的交通事故。
occur to sb./sth.指“某种思想等呈现于某人的知觉中”。
Didn’t it occur to you to phone them about it？ 你难道就没想过给他们打个电话？
It never occurred to her to ask anyone. 她从未想到去问问别人。
A good idea occurred to me. 我想起了一个好主意。
3).take place phr. v. 发生，举行
主要用于事先计划好的事情。表示“举行”的意思，带有非偶然性。
The Olympics take place every four years.奥运会每四年举行一次。
In 1919, the May 4th Movement took place in China．一九一九年，中国发生了五四运动。
Great changes have taken place in China.
中国发生了翻天覆地的变化。
The parade will take place on Sunday, rain or shine.
庆祝游行定于星期日举行，风雨无阻。
The meeting will take place on Sunday. 会议星期日举行。
Elections take place every four years. 每 4 年举行一次选举。