Sigma
[计] 求和\\n[医] σ(希腊文第十八个字母)
🗣️ 情景例句
And if you don't?
要是你找不到呢？
On the morning of the next day he went to New York.
第二天早晨，他去了纽约。
Children often love to play this game.
孩子们常爱玩这种游戏。