When a brief pulse of electricity is sent to the read/write head it flips on a tiny electromagnet for a fraction of a second.

当一个简单的电脉冲被送到读写头,它会短时间内出现一个小的电磁。

哈佛公开课 - 计算机科学课程节选

so ta retail bank sells the mortgage and then the retail banks flips it to Fannie Mae and Freddie Mac which essentially package huge numbers of the mortgages across the countries.

所以商业零售银行发行贷款，they…,然后商业零售银行将贷款转手,卖给房地美和房利美,事实上是收集了,大量的,全国的房贷。

斯坦福公开课 - 经济学课程节选