`Set sb. doing sth.` 是一个英语动词短语，表示“使（引起）某人开始做某事”，通常强调的是启动或开始一个动作。这个短语中的 "set" 是动词，意为“设置”或“使处于某种状态”，而 "sb." 是代词，代表“某人”，"doing sth." 则是现在分词形式，表示正在进行的动作。

**用法示例：**

1. **基本用法：**

   - The teacher set the students discussing the topic in groups. (老师让学生们分组讨论这个话题。)

   - The alarm clock set me waking up at 6 a.m. every day. (闹钟让我每天早上6点醒来。)

2. **被动语态：**

   - The new policy was set putting a stop to illegal logging. (新政策使得制止非法砍伐成为可能。)

   - The accident set her thinking about her career choices. (那次事故让她开始思考自己的职业选择。)

3. **否定句：**

   - Don't set me worrying about unnecessary details. (别让我担心那些不必要的细节。)

   - The medication won't set him sleeping; it's just a pain reliever. (这种药不会让他睡觉，它只是一个止痛药。)

4. **疑问句：**

   - What set him off on this tangent? (是什么让他突然转移话题了呢？)

   - How did they set you dreaming about becoming an astronaut? (他们是如何让你梦想成为一名宇航员的？)

**同义词辨析：**

1. **Get sb. doing sth.**：与 "set sb. doing sth." 类似，也表示“使某人开始做某事”。例如：

   - She got him talking about his childhood memories. (她让他谈论起他的童年记忆。)

2. **Start sb. doing sth.**：同样表示“开始让某人做某事”。例如：

   - The performance started everyone laughing. (这场表演让大家笑得前仰后合。)

3. **Cause sb. to do sth.**：强调导致或引起某人去做某事的结果。例如：

   - The book caused her to reflect on her life choices. (这本书使她反思自己的生活选择。)

4. **Prompt sb. to do sth.**：表示激发或促使某人去做某事。例如：

   - The news prompted him to donate money to charity. (这则新闻促使他向慈善机构捐款。)