so-and-so

例句：

1. 1. He's always so-and-so when he talks to his friends.
   他和朋友说话时总是那个样子。
2. 2. She's a so-and-so in the office.
   她在办公室是个无名小卒。
3. 3. We need to find someone who can help us with this problem.
   我们需要找个人来帮我们解决这个问题。