含义
Deep in thought 是一个英语习语，用来描述某人正在非常专注地思考问题，通常表现为沉默、眼神放空或一动不动。
基本结构
该短语通常作表语或状语使用，常见结构包括：
- 主语 + be + deep in thought
- 主语 + sit/stand/walk + deep in thought
例句
- She sat by the window, deep in thought.
- He was deep in thought and didn’t hear me call his name.
- They walked through the park, both deep in thought.
常见搭配
- lost in thought（与 deep in thought 含义相近）
- sit/stand/walk + deep in thought
- appear/seem + deep in thought
注意事项
不要将 deep in thought 与 deeply thinking 混淆。前者强调状态（沉浸于思考中），后者强调动作（正在深入思考）。在地道英语中，deep in thought 更自然、更常用。