Quaternary period
un. 第四纪\\n
🧩 词语组成解析
a. 四个一组的, 四元的, 四价的, 季的\\n[计] 四进制的, 四元的
period
['pɪrɪəd]
n. 时期;（一段）时间;学时;句号;
adj. 具有某个时代特征的;（关于）过去某一特定历史时期的;（家具、服饰、建筑等）某一时代的;
peri周围，靠近+od道路→周期
🗣️ 情景例句
My son must have put you to a lot of trouble.
我儿子一定给你带来不少麻烦。
Oh well, better luck next time.
算了，下次的运气会更好。
and we have to lower into the ground and haul out of the ground great lengths of drill pipe which are rotated by an engine at the top and are fitted with a cutting bit at the bottom.
我们必须把很长的钻杆一节节地钻入地下，然后再从地下拉出来。钻杆顶部安装的发动机带动钻杆旋转，它的底部装有钻头。