A cleft sentence (/kleft sentəns/) is a sentence consisting of (at least) two clauses, one of which is a cleft clause. They are used for emphasis, and transform a short sentence into as longer, more emphatic form.
|It cleft||it + be + noun + relative pronoun + verb||"It was you who stole my ring"|
|Wh- cleft||What + noun + Verb(s) + be||"What you need is a haircut", or "What she should do is get a life"|
|?||The + noun + defining relative clause + [be]||* "The pub (that/which) my friends like is over there"