THAT & WHICH as Pronouns introducing Relative Clauses

ESL learners who are not conversant with the intricacies of English speech- rhythm are often confused when it comes to a choice between that and which to introduce relative clauses . They tend to use these pronouns interchangeably ! Are that and which really different?

That as a relative pronoun appeared in English during the Middle English period . This word has phonetic features enabling it to serve as an introducer to defining relative clauses . The defining relative clause and the rest of the sentence belong to the same tone-group . So the glide from the subject Noun Phrase to the relative clause is a smooth one .For example

The book that I read yesterday is a novel by R.K.Narayan.

The clause "that I read " is a defining relative clause as it is essential for getting at the meaning of the sentence. . The relative clause defines or limits the antecedent- book . The pronoun that,by virtue of its phonetic features , ensures a smooth flow from subject NP to the relative clause. No wonder, then, that the English language accepted that as a better choice than which for introducing defining relative clauses! Which is used for defining relative clauses only in written English of very formal style.

Relative clauses may sometimes introduce parenthetical ideas , that is to say, ideas that are not an essential part of the sentence . That clause may be called a non-defining relative clause . It merely provides additional information . So it has to be signalled in some way . English speakers use a pause to signal this, and the relative clause that follows it belongs to a different intonation group . By virtue of its phonetic features which is a better choice than that to indicate the break In written English the non-defining relative clause is marked off from the rest of the sentence with commas . Look at this example

Mobile phones , which are so useful, are often misused by students .

My car , which I bought a year ago, is running well.

Non-defining relative clauses seek to squeeze a lot of information in a single sentence . It is more appropriate in formal style English than in conversational English . The sentences given above can be reworded in spoken English as follows :

Mobile phones are misused by students . It is a pity! They are so useful!

My car is running well. You know , I bought it a year ago .


Thank you for your visit!