do a double take 仔细看才發現

I did a double take , I couldn't believe it was her. 我一时没会意过来, 簡值不敢相信這是她

She suddenly caught the reference and did a double take. 他突然注意到了那张证明，于是就又认真看了一遍。

Your double. 跟你很像。

I met someone at a party who was your double. 我在聚会上遇到一个长得和你很像的人。

John is the double of his father. 约翰长的酷是他父亲。