IELTS grammar: Cleft Sentences for Emphasis

A cleft sentence takes information that could be expressed in one plain clause and splits it into two clauses specifically to throw emphasis onto one particular element. This matters for scoring because Task 2 essays are full of claims that could be stated flatly but land with much more force when a specific element is foregrounded — cause, blame, priority, or the single factor that actually matters most. The error pattern worth naming upfront is not that candidates get the meaning wrong; it's that many either avoid cleft sentences entirely, missing an easy way to signal advanced sentence control, or attempt them and make a subject-verb agreement slip inside the clause, which is the one grammatical trap this structure consistently sets. Two forms cover almost every case that comes up in exam writing: the it-cleft, built around "It is/was X that...," and the what-cleft (sometimes called a pseudo-cleft), built around "What X does/needs/matters is Y."

The it-cleft takes the form "It is/was + [the emphasised element] + that/who + [rest of the clause]." "It was the lack of funding that caused the project to fail" emphasises "the lack of funding" far more sharply than the plain equivalent, "The lack of funding caused the project to fail," because the cleft structure isolates that one cause and presents it as the answer to an implicit question — what actually caused this? Use "who" rather than "that" when the emphasised element is a person: "It was the previous minister who introduced this policy," not "It was the previous minister that introduced this policy," though in practice both are widely used and only "who" is fully safe for a human subject in formal writing. Tense flexibility is one of the it-cleft's real strengths: "It is the lack of funding that caused the failure" and "It was the lack of funding that caused the failure" are both grammatical, with the tense on "is/was" reflecting whether the emphasis itself is framed as a current judgement or a past one, independent of the tense inside the following clause.

The it-cleft becomes especially powerful in its contrastive form, pairing "not X but Y": "It is not a lack of resources but a lack of coordination that has slowed the response." This single sentence does the work of an entire argument — conceding one plausible explanation while asserting the real one — far more efficiently and more memorably than listing both factors as though they carried equal weight. This contrastive it-cleft is one of the highest-value sentence patterns available for a Task 2 conclusion or a topic sentence that reframes a common assumption, precisely because it makes an arguable, specific claim rather than a safe, general one.

The what-cleft (pseudo-cleft) moves the emphasised element to the very end of the sentence, building anticipation toward it: "What the government needs to address first is the housing shortage." The structure is "What + [subject] + [verb] + is/was + [emphasised element]." A frequent variant foregrounds an action rather than a single noun: "What this policy actually does is shift the financial burden onto local authorities rather than removing it." Because the emphasised element sits at the very end, it receives the sentence's natural stress point, which is why this form works especially well for a sentence you want a reader to pause on before moving to the next paragraph. A related variant places the emphasis on the whole embedded clause rather than a single noun phrase, particularly when followed by an infinitive: "What most families need is to feel confident that their children are safe," where the emphasised element after "is" is itself an infinitive clause rather than a plain noun — this pattern is fully grammatical and common, but candidates sometimes force a noun phrase where an infinitive clause would actually be more natural, producing an awkward "What most families need is confidence of safety for their children" instead.