Perioidic system
[机] 周期系
🧩 词语组成解析
🗣️ 情景例句
It's so good to have you home again ...
真高兴 ，你又回家了……
Money is the key that opens all doors.
金钱是打开一切门户的钥匙。
People woken during these periods of eye-movements generally reported that they had been dreaming.
在眼球活动期间被叫醒的人都说自己在做梦；