A Cleft Sentence (cleft, past participle of cleave = split) is a sentence that has been split into two clauses – a main clause and a subordinate clause – in order to emphasize one part of it. This part is often referred to as the “focus”.
It is her kindness that I will remember.
– focus on “her kindness”
The reason why I’ve come is to discuss my future with you.
– focus on “discuss my future”
What we now need are actions rather than words.
– focus on actions
All I want for Christmas is YOU.
– focus on “you”
Structure & Usage
Cleft structures are more common in written than spoken English. This is because in spoken English we can use intonation to express emphasis. In written English intonation is of no use so we resort to this grammatical structure to help focus on a particular part of a sentence and to emphasize what we want to say. This is usually done by means of introducing it or building up to it with a kind of relative clause.
There are different types of clefts, but perhaps the most common, and the easiest to recognize, are the wh-clefts and the it-clefts.
The one who is causing trouble is John.
It’s John who’s causing us trouble.
Here is a typical pattern of a cleft sentence:
it + be + X + subordinate clause
Let’s pretend that you took your suit to the dry-cleaners. A couple of days after you go back to collect it and find that they have ruined it. When recounting this you could simply make a statement like:
The dry-cleaner ruined my suit.
This is a simple sentence that tells us about an event in a fairly balanced way. But perhaps you are angry, upset, or annoyed at the dry-cleaner and want to express it. To do this you can use a cleft sentence which places the emphasis on the dry-cleaner, not the suit or the fact that it got ruined. Your cleft sentence could be:
It was the dry-cleaner who ruined my suit.
This cleft sentence expresses the same information in the original simple sentence “The dry-cleaner ruined my suit” by way of a main clause “It was the cleaner …” and a subordinate clause “… who ruined my suit.” but places the most important piece of information closer to the beginning of the sentence.
Therefore X and the subordinate clause in the pattern above carry the same meaning as their corresponding simple sentence. However, the primary focus of the cleft construction is on an element, often marked by intonation, that introduces new information. This element appears either as X or in the subordinate clause.
Pseudo & Inverted Pseudo Clefts
Pseudo-clefts are a kind of cleft sentences in which the subordinated clause is a relative clause headed by an interrogative word.
wh-relative clause + be + X
Inverted pseudo-clefts are sentences in which the order of the two constituents is reversed.
X + be + wh-relative clause
What John gave to Mary were flowers.
Flowers were what John gave to Mary.
Clauses in English Grammar – an overview of what a clause is and how many types there are
Subordinate Clauses in English Grammar – a closer look at this particular type of clauses