跟介詞，如：What happened with sb.？或者：what happened to sb.？
意思是：某人出什麼事情了？
what happened to him?
意思是：他發生了什麼事
happen是不及物動詞,它的用法常見的有如下幾種情況：
1. 表示“某地(某時)發生了什麼事”,常用“sth.+ happen +地點/時間”這一結構來表達,此時主語應是事情.例如：
The story happened in 2003. 這個故事發生在2003年.
An accident happened in that street. 那條街上發生了一起事故.
2. 表示“某人出了某事(常指不好的事)”,要用“sth.+ happen+to sb.”這一結構來表達.例如：
A car accident happened to her this morning. 今天上午她發生了交通事故.
What happened to you? 你怎麼啦?
3. 表示“某人碰巧做某事”,要用“sb.+ happen+ to do sth.”這一結構來表達.例如：
I happened to meet a friend of mine in the street yesterday. 昨天我碰巧在街上遇到了我的一個朋友.
4. happen表示“碰巧或恰巧發生某事”時,還可用“It happens / happened that...”這一結構來表達.例如：
It happened that Brian and Peter were at home that day. 碰巧那天布萊恩和彼得在家了.
It happened that he had to take part in a meeting that afternoon. 碰巧那天下午他不得不參加一個會議.
注：that從句中的主語是人時,此種結構可以與“sb.+ happen + to do sth.”結構互換.例如：
It happened that Brian and Peter were at home that day. = Brian and Peter happened to be at home that day.
跟介詞，如：What happened with sb.？或者：what happened to sb.？
意思是：某人出什麼事情了？
what happened to him?
意思是：他發生了什麼事
happen是不及物動詞,它的用法常見的有如下幾種情況：
1. 表示“某地(某時)發生了什麼事”,常用“sth.+ happen +地點/時間”這一結構來表達,此時主語應是事情.例如：
The story happened in 2003. 這個故事發生在2003年.
An accident happened in that street. 那條街上發生了一起事故.
2. 表示“某人出了某事(常指不好的事)”,要用“sth.+ happen+to sb.”這一結構來表達.例如：
A car accident happened to her this morning. 今天上午她發生了交通事故.
What happened to you? 你怎麼啦?
3. 表示“某人碰巧做某事”,要用“sb.+ happen+ to do sth.”這一結構來表達.例如：
I happened to meet a friend of mine in the street yesterday. 昨天我碰巧在街上遇到了我的一個朋友.
4. happen表示“碰巧或恰巧發生某事”時,還可用“It happens / happened that...”這一結構來表達.例如：
It happened that Brian and Peter were at home that day. 碰巧那天布萊恩和彼得在家了.
It happened that he had to take part in a meeting that afternoon. 碰巧那天下午他不得不參加一個會議.
注：that從句中的主語是人時,此種結構可以與“sb.+ happen + to do sth.”結構互換.例如：
It happened that Brian and Peter were at home that day. = Brian and Peter happened to be at home that day.