这是代词what的一种特殊用法.即这里的what=the things that,what在宾语从句中做主语.
we were curious to find out what had happed=we were curious to find out the things that had happed.
这是代词what的一种特殊用法.即这里的what=the things that,what在宾语从句中做主语.
we were curious to find out what had happed=we were curious to find out the things that had happed.