Arithmetic series
等差级数
🧩 词语组成解析
🗣️ 情景例句
Yes, but the number's no longer in service.
打过，但那个号码是空号。
Our own actions are our security, not others' judgements.
我们的行为是自己的保证而不是别人的鉴定。
The group of girls all moved on and had a good drink of tea together, from a modern thermos!
这一群女孩一块儿去享受了一番茶水。她们用得是现代的热水瓶！