What they found,in attempting to model thought,is that the human brain’s roughly one hundred billion

题目

What they found,in attempting to model thought,is that the human brain’s roughly one hundred billion nerve cells are much more talented -- and human perception far more complicated -- than previously imagined.
之中的破折号有什么用?有没有其他的表达形式

答案

我认为第一个破折号表示解释,第二个表示加强语气的作用.如果不用就达不到作者要表达的效果.