Cleft Sentences: It-Clefts, What-Clefts and Examples

In speech we can emphasise any word just by stressing it: MARIA lost the keys. In writing, stress is invisible, so English uses grammar instead. A cleft sentence takes one ordinary sentence and splits (or cleaves) it into two clauses. The first clause points at the information we want to highlight; the second clause gives the rest.

Cleft sentences do three main jobs. They correct a wrong idea (It was Maria who lost them, not me). They contrast two things (What I want isn't money, it's time). And they introduce a topic or explanation in a clear, organised way (What we need to discuss today is the budget).

There are two main types: it-clefts and wh-clefts (also called pseudo-clefts). Both appear in conversation, presentations, essays and journalism.

Build an it-cleft with It + be + focus + that or who + the rest of the sentence. The tense of be usually matches the time of the situation: It is Monday that suits me best, It was last week that we met.

You can focus on the subject, the object, a time, a place, a reason or almost any phrase. You cannot normally focus on the main verb with an it-cleft; use a what-cleft for that (What she did was resign).

When the focus is the subject, the verb in the second clause agrees with it: It's the neighbours who are noisy, It's Ben who is late. With a pronoun focus, informal English uses the object form: It was me who called. The formal version, It was I who called, sounds old-fashioned in most situations.

The second clause is similar to a relative clause; see relative clauses with who, which and that.

A very useful it-cleft is It wasn't until + time + that. It means that something happened only at that later time, and it often shows surprise or delay.

Compare: I didn't understand the joke until the next day. It wasn't until the next day that I understood the joke. The meaning is the same, but the cleft puts the focus on the time.

This pattern is a less formal alternative to inversion with Not until (Not until the next day did I understand); see inversion.

A what-cleft starts with What + subject + verb, then be, then the focus: What I need is a coffee. The what-clause works like a noun meaning the thing that.

To focus on an action, use What + subject + do + be + verb: What he did was apologise. After was, the bare verb is most common in speech; to + verb is also correct (What he did was to apologise). To describe a whole event, use What happened was (that) + clause.

All works the same way but means the only thing: All I said was hello. All you have to do is press this button. All-clefts often sound like you are defending yourself or making something seem simple.

You can also reverse a what-cleft and put the focus first: A good night's sleep is what you need. This is common when the focus links back to something already mentioned.

Instead of what, we can use a general noun with a relative clause: the thing (that), the person who, the place where, the time when, the reason (why), the way. These are very natural in conversation, and they are the way to focus on people, places and times, because what refers only to things.

The reason (why) ... is that is common for explanations. In careful writing, use is that rather than is because: The reason I'm late is that the bus broke down. The reason ... is because is common in speech, but many teachers and editors see it as repetitive.

The short phrase The thing is, ... is a spoken way to introduce a problem or an important point: The thing is, I don't have time.

Cleft sentences are everywhere in natural speech, especially for correcting, explaining and organising. Listen for What I mean is..., What I'm saying is..., All I know is..., It's not that I don't like it, it's just... and The problem is....

In presentations, what-clefts help you signpost: What I'd like to do today is.... What we found was.... In essays, an it-cleft can highlight your key point in one sentence. Like any emphasis tool, use them where the emphasis matters; too many make writing heavy. For related ways to organise information, see nominalization and ellipsis and substitution.