Cleft sentences are used to help us focus on a particular part of the sentence and to emphasise what we want to say by introducing it or building up to it with a kind of relative clause.

Because there are two parts to the sentence it is called cleft (from the verb cleave) which means divided into two.

Cleft sentences are particularly useful in writing where we cannot use intonation for purposes of focus or emphasis, but they are also frequently used in speech.

Cleft structures include the reason why, the thing that, the person/people who, the place where, the day when and what-clauses which are usually linked to the clause that we want to focus on with is or was. which are usually

Compare the following sets of sentences and notice how the cleft structure in each case enables us to select the information we want to focus on:

    * I've come to discuss my future with you.

    * The reason why I've come is to discuss my future with you.

    * Your generosity impresses more than anything else.

    * The thing that impresses me more than anything else is your generosity.