Sigma
[计] 求和\\n[医] σ(希腊文第十八个字母)
🗣️ 情景例句
The boxes of presents.
那些礼物盒。
I can give you one for $24.00 a day or $158.00 a week.
租一辆一天24美元，一周158美元。
The ideal to be aimed at was to devise an instrument that could record with a pen on paper,
当地震发生时，它能用笔在纸上记录下