Sif
abbr. selective identification feature 选择识别特征
🗣️ 情景例句
Here's $ 1000 for the trip. Use some of it for stamps.
这里是1000美元，给你当旅费。要把一些用来买邮票啊！
He can run as fast as Jim.
他跑的和吉姆一样快。
The Smiths are my neighbors.
史密斯一家是我的邻居。