"happen"用于描销或述事件的发生，强调事件本身，不涉裂斗逗及特定的主体。
"happen to"用于描述事件偶然发生在特定的主体身上，强调事件与某人的关联或影响。
大家可以先看下面的表格了解一下 happen和happen to 吧：
例子1：A car accident happened outside my house yesterday. (昨天我家外面发生了一起车祸。)
例子2：Unexpected delays can happen during your journey. (旅途中可能会出现意外的延误。)
例子1：I happened to find your missing keys in the drawer. (碰巧我在抽屉里找到了你丢失的钥匙。)
例子2：She happened to be at the same party last night. (她昨晚碰巧也在同一个派对上。)
例子1：It's strange how coincidences happen. (巧合发生的方式很奇怪。)
例子2：Do you know why earthquakes happen? (你知道为什么会发生地震吗？)
例子1：I happened to meet an old friend on the way to work. (我偶然在上班的路上碰到一个老朋友。)
例子2：She happened to see the same movie three times. (她偶然看了三次同一部电影。)
例子1：Accidents happen without any warning. (事故总是突然发生的。)
例子2：Unexpected opportunities can happen in life. (生活中可能会突然出现机会。)
例子1：He happened to get the job after a chance encounter with the CEO. (他在与首席执行官偶然相遇后得到了这份工作。)
例子2：It happened to rain heavily on our picnic day. (偏偏在我们野餐的日子下起了大雨。)
例子1：Events like these happen all the time. (这样的事件经常发生。)
例子2：Don't worry; accidents happen occasionally. (别担心，事故偶尔会发生。)
例子1：Did it happen to you too? (这也发生在你身上了吗？)
例子2：It won't happen to me again. (这种情况不会再发生在我身上了。)
标签：happen
