What is a What-Clause?
A "what-clause" is a specific type of noun clause that begins with the word what. We use it to emphasize a particular part of a sentence. It acts like a spotlight, drawing attention to the most important information.
These sentences are also called pseudo-cleft sentences. A normal sentence is "cleft" (split) into two parts to create focus.
- Normal sentence: I need a good holiday.
- With a what-clause: What I need is a good holiday.
The second sentence puts a strong focus on "a good holiday."
The Structure
The most common structure involves a what-clause acting as the subject, followed by the verb be, and then the emphasized information.
What-Clause (Subject) + be + Emphasized Information
In this structure, what means "the thing that" or "the things that."
| Normal Sentence | Emphatic Sentence with What-Clause |
|---|---|
| I said that. | What I said was that. |
| You need to rest. | What you need is to rest. |
| He bought a new car. | What he bought was a new car. |
What Can We Emphasize?
1. Emphasizing the Object or Complement
This is the most common use. The what-clause contains the subject and verb, and the object is placed after be.
- She loves reading books. → What she loves is reading books.
- I want a cup of tea. → What I want is a cup of tea.
2. Emphasizing the Action (Verb)
To emphasize a verb, we often use the structure What + subject + do/does/did + be....
- He broke the window. → What he did was break the window.
- She is writing a novel. → What she is doing is writing a novel.
Notice that after was/is, we often use the base form of the verb (break) or the gerund (writing).
3. Inverted Structure
You can also reverse the structure for a similar effect.
Emphasized Information + be + What-Clause
- A good holiday is what I need.
- That's what I said.
- This is what you need to do.
Verb Agreement
The verb be after the what-clause usually agrees with the noun that follows it.
- What I need is a new pen. (Singular)
- What I need are some new pens. (Plural)
However, in informal speech, it's very common to use is for both.
- Informal: What I need is some new pens.
Common Errors and How to Fix Them
| ✗ Incorrect | ✓ Correct | Why |
|---|---|---|
| What I need it is a drink. | What I need is a drink. | The what-clause is the subject; you don't need an extra "it." |
| What does he want is a new job? | What he wants is a new job. | A what-clause is a statement, not a question. Use statement word order. |
| The thing what I said was true. | What I said was true. OR The thing that I said was true. | Don't combine "the thing" and "what." "What" already means "the thing that." |
Summary
| Structure | Purpose | Example |
|---|---|---|
| What-clause + be + info | Emphasizes the information at the end. | What I believe is that everyone deserves a chance. |
| Info + be + what-clause | Emphasizes the information at the beginning. | That is what I believe. |
| What...do + be + verb | Emphasizes an action. | What we did was watch a movie. |
💡 The key takeaway: Use a what-clause when you want to make one piece of information in your sentence stand out. It's a powerful tool for focus and emphasis.