happen表示“碰巧或恰巧發(fā)生某事”時(shí),可用“It happens / happened that...”這一結(jié)構(gòu)來(lái)表達(dá).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(gè)會(huì)議.
so只是個(gè)副詞,為了表明事情發(fā)生的偶然程度,就是說(shuō),在表達(dá)“太巧了……”的時(shí)候,加so,加了so的時(shí)候,that后面的從句通常強(qiáng)調(diào)的是“如此巧合”造成的“結(jié)果”.
“There happened to be nobody in the house on fire.”中,happened to 依然表示“碰巧”的意思,但是個(gè)用在“There be”句型中的獨(dú)立成分.
“It (so) happened that.”之所以用“it”,是因?yàn)閠hat后面是從句,it做的是that后從句的形式主語(yǔ)!
如果把“There happened to be nobody in the house on fire.”這句改成從句形式,那就是“It happened that there was nobody in the house on fire.”