Singleton substitution
[计] 唯一替换
🧩 词语组成解析
n. 一个, 独生子, 独身
substitution
[ˌsʌbsti'tju:ʃən]
n. 代替;代用;替换;<化>取代（作用）;
🗣️ 情景例句
Excuse me.
失陪。
He that climbs high falls heavily.
爬得高，跌得重。
Sure. We were in the same class.
当然认识。我们同班呢。