As a general rule, the relative pronoun who refers to persons, which refers to things, and that may refer to either persons or things. For additional guidelines, see the Usage Notes below.
- Nonrestrictive Relative Clause and Restrictive Relative Clause
- Using the Different Forms of Pronouns
- "Which," by James Thurber
- Who and Whom
- Whoever and Whomever
- Wh- Words
- The man who just left drives a Pacer, which once was called "the car of the future."
- "An association of men who will not quarrel with one another is a thing which has never yet existed, from the greatest confederacy of nations down to a town meeting or a vestry." (Thomas Jefferson)
- The movie industry was run for many years by people who grew up in a business that they loved and understood.
- Usage of That and Which in American English and British English
"Many budding grammarians express confusion over the usage of that and which. Strictly speaking, they are interchangeable except that which should never refer to people. However many [American] usage manuals recommend a convention for the use of these pronouns to help readers distinguish between restrictive and nonrestrictive information in sentences. The relative pronoun that should be used in restrictive subordinate clauses. Remember that restrictive information is essential to the meaning of a sentence and cannot be removed without changing that meaning. The relative pronoun which should be used in nonrestrictive subordinate clauses. Nonrestrictive information is not essential and can be removed without significant change to the meaning of a sentence. Please remember that nonrestrictive information must be set off from the rest of the sentence by commas."
(Michael Strumpf and Auriel Douglas, The Grammar Bible. Owl Books, 2004)
"Which informs, that defines. This is the house that Jack built. But This house, which Jack built, is now falling down. Americans tend to be fussy about making a distinction between which and that. Good writers of British English are less fastidious. ('We have left undone those things which we ought to have done.)"
(The Economist Style Guide, 10th ed. Profile Books, 2005)
"The discrimination between which and that and between who and that is one of the marks of a stylist.
"With the caution that 'the tendency to appropriate who and which to persons and things respectively often outweighs other considerations; thus, 'People who live in glass houses' is preferred to 'people that'; this is particularly the case with those, they, and other pronouns of common gender. 'Those who are in favour of this motion' is more usual than 'those that' [but this may be partly because they who and those who are formulas] . . ..
"In speech, the use of which for that is less reprehensible, for intonation will convey the sense. But in the written language the need of discrimination between the two classes described is often felt, and the non-observance of the distinction is liable to lead to misunderstanding. Example: 'All the members of the Council who were also members of the Education Board, were to assemble in the Board-room.' This would normally imply that all members of the Council were members of the Education Board. 'That' instead of 'who' would clearly express the meaning intended, which is that 'those who are members of the Education Board as well as of the Council were to assemble."
(Eric Partridge, Usage and Abusage: A Guide to Good English, 1973; rev. by Janet Whitcut. Norton, 1995)
- Omission of That (the Zero Relative Pronoun)
"When that introduces a relative clause it can be omitted--and often is, depending on both grammatical and stylistic factors. It often disappears when it's the object of the relative clause, as in:
The TV program (that) we saw last night had a powerful impact on us.Compare the obligatory use of that in:
A TV program that had a powerful impact on us was shown last night.In the second sentence that is the subject of the relative clause and must be expressed in current written English. Yet the deletion of that as object pronoun is normal in conversation, and these days common in writing . . .."
(Pam Peters, The Cambridge Guide to English Usage. Cambridge University Press, 2004)>/li>
(a) Nan's book, _____ was published in May, is now a bestseller.
(b) "America is the only country _____ went from barbarism to decadence without civilization in between." (Oscar Wilde)
(c) A writer is a lucky person _____ has found a way to talk without being interrupted.