Question 1

What is a do-cleft sentence?

Accepted Answer

A do-cleft emphasises the action in a sentence by using the structure "What + subject + do/did + is/was + verb." For example, "He apologised" becomes "What he did was apologise" — the focus shifts to the act of apologising. Do-clefts are effective when you want to highlight that a specific action was significant, surprising, or important: "What the government did was reverse its own policy." They also work well in contrast: "What she did wasn't complain — she found a solution." The "do" element refers to the general action, while the verb after "was" specifies exactly what that action was. Do-clefts are an advanced structure tested at C1 level.

Question 2

Do I use the bare infinitive or "to" after "was" in do-clefts?

Accepted Answer

Both forms are grammatically correct: "What he did was leave" (bare infinitive) and "What he did was to leave" (to-infinitive). In everyday spoken English, the bare infinitive is far more common and sounds more natural. The to-infinitive is slightly more formal and may appear in written English. Cambridge examiners accept both forms, so you do not need to worry about which one to use in an exam. However, note that when the do-cleft uses a present form — "What you need to do is call the helpline" — the bare infinitive is almost always preferred. Do not use the past tense after "was": "What she did was resigned" is always incorrect — say "What she did was resign."

Question 3

What is an event cleft and when should I use one?

Accepted Answer

An event cleft uses "What happened" or "What happens" to frame an entire event as the focus: "What happened was that the train broke down and everyone had to walk." The word "that" after "was" is optional but often included for clarity. Event clefts are especially useful in storytelling and explanations because they create narrative structure: "What happened next was extraordinary." They also work in formal reports: "What occurred was a series of communication failures." Use event clefts when you want to frame an entire situation — not just a single action — as the important information. They differ from do-clefts, which focus on one specific action or verb.

Do-Cleft & Event Cleft Exercises

Quick Rule

Continue Practising

Cleft Sentences Error Correction

It-Cleft: Subject Focus

Wh-Clefts

-ed vs -ing Adjectives

Conditionals

Present Perfect