Clefting is a grammatical construction used to emphasize a specific part of a sentence. It typically involves splitting a sentence into two clauses, often using the phrase "It is" or "It was" to highlight the important element. For example, in the sentence "It was John who won the race," the focus is on John as the winner. This technique can also help clarify information by rearranging the sentence structure. Clefting allows speakers and writers to draw attention to particular details, making communication more effective. It is commonly used in both spoken and written language to enhance clarity and emphasis.