视频对白：

That people who dug this well did it completely by hand. God knows how long it take them.

当时挖这口井的人靠的完全是双手。天知道花了多长时间才完工。

今天要学习的词组为：by hand

意为“用手的，手工的 ”。

例句：
1. You can pump up the tyres by hand or with this special machine.
这可以用手或用这个特殊的机器给车胎打气。

2.Farmers used to thrash their wheat by hand.
农民过去用手打麦脱粒。