I couldn't understand how something this terrible could have happened.

问题描述:

I couldn't understand how something this terrible could have happened.
其它都好说,那个“how something this terrible”怎么解释?

this 此处是一个语气词,不是“这个”的意思,而是 “这么的”“到这样的地步的”意思.
相当于一个形容词,与后面的terrible共同修饰something(something是要定语后置的)
我不明白,这么糟糕的事情怎么会发生.