by词性是介词

例句如下，请仔细体会

1、

He arrived at the solution by a simple process of deduction.

他通过一番简单的推理得出了解决问题的方法。

2、

It works by remote control.

它通过遥控工作。

3、

She'll have had the results by now.

她现在应该知道结果了。