分裂句把一个普通句拆成两个分句，让其中某个信息点成为焦点。英语常用两种结构来实现这一点：一种以 It was/is... 开头，另一种以 What... 开头。

简单来说：Maria called me 是中性表达。It was Maria who called me 把 Maria 推到焦点位置——信息相同，重点不同。

it 分裂句：It was/is + 强调部分 + that/who

it 分裂句的结构是：It + be + 被强调的信息 + that/who + 句子的其余部分。它几乎可以强调句子的任何成分：主语、宾语、时间或地点：

普通句 it 分裂句，强调……
Maria called me yesterday. It was Maria who called me yesterday.（主语）
Maria called me yesterday. It was me that Maria called yesterday.（宾语）
Maria called me yesterday. It was yesterday that Maria called me.（时间）

强调人的时候，日常英语中 who 和 that 都可以用（It was Maria who called / It was Maria that called）。强调事物、时间或地点时，用 that，绝不用 who：✅ It was the phone call that surprised me，绝不说 ❌ It was the phone call who surprised me。

中文里有一个很像的表达：“是……的”句式，比如“是玛丽打的电话”，也可以把某个信息挑出来强调。不过英语 it 分裂句还要注意后面的 who/that：强调人可以用 who 或 that，强调事物、时间、地点通常用 that；中文没有这类关系词的选择，用法更简单统一。

what 分裂句：What... is/was + 强调部分

what 分裂句（也叫准分裂句）把一个以 What 开头的分句放在最前面，充当主语，后面接 be 和被强调的信息：

  • I need a break. → What I need is a break.
  • His reaction surprised me. → What surprised me was his reaction.
  • She wants to travel more. → What she wants is to travel more.

what 分裂句通常强调一件事、一个动作或一个想法，而不是强调是“谁”做了这件事。要强调是谁做的，更自然的选择是 it 分裂句：✅ It was Maria who called，而不是 ❌ What called me was Maria。

All 可以替换 What，带来“仅此而已”的更强限定意味：All I need is a break（相比之下 What I need is a break 语气更中性）。

两种结构怎么选

it 分裂句是更灵活的工具，可以强调主语、宾语、时间或地点。what 分裂句范围更窄：它强调的通常是 What 分句背后那个问题的答案——某件事、某个动作或某个想法（What do you need? → What I need is...），所以通常不适合用来强调“是谁做的”或某个确切的时间点；这类情况下，it 分裂句仍然是更自然的选择：It was yesterday that Maria called me.

常见错误

  • ❌ It was Maria which called me. → ✅ It was Maria who called me.（which 指物，不指人）
  • ❌ What I need it is a break. → ✅ What I need is a break.（不需要多余的 it——What 分句本身就是主语）
  • ❌ What called me was Maria. → ✅ It was Maria who called me.（what 分裂句通常不用来强调某个人）
  • ❌ It was yesterday who Maria called me. → ✅ It was yesterday that Maria called me.（who 只用于人；表示时间和地点要用 that）

小测验

把每个句子改写成分裂句，强调括号里的词或短语。

  1. Tom broke the window. (Tom — it 分裂句)
  2. I really need some sleep. (some sleep — what 分裂句)
  3. We're meeting at the café. (at the café — it 分裂句)
  4. The delay annoyed her the most. (the delay — what 分裂句)
查看答案
  1. It was Tom who/that broke the window.
  2. What I really need is some sleep.
  3. It's at the café that we're meeting.
  4. What annoyed her the most was the delay.

重点回顾

  • 分裂句把一个普通句拆成两个分句，用来强调一个具体信息。
  • it 分裂句（It was/is + 强调部分 + that/who）比较灵活，可以强调主语、宾语、时间或地点。强调人时用 who 或 that；强调事物、时间、地点时只能用 that，绝不用 who。
  • what 分裂句（What... is/was + 强调部分）强调一件事、一个动作或一个想法，而不是强调是谁做了这件事。
  • 在 what 分裂句中，All 可以替换 What，带来更强的限定意味（All I need is...）。
  • 两种结构表达的基本事件或信息与原句相同，只是改变了强调的重点——尤其是 it 分裂句，往往还带有对比意味（“是玛丽打的电话，不是别人”）。