essential and non-essential modifiers (That and which)

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The relative pronouns in English include who, whom, whose, which, whomever, whatever, and that. (Note: Not all modern syntacticians agree that that is a relative pronoun.) What is a compound relative, including both the antecedent and the relative, and is equivalent to that which; for example, "I did what he desired" means the same as, "I did that which he desired."

In some contexts, there may be a choice between two or more of these forms. The choice of relative pronoun may carry additional meaning or draw a number of distinctions.

Contents [hide]
1 Variables in the basic relative clause
1.1 Human or non-human
1.2 Restrictive or non-restrictive
1.3 Grammatical case
1.4 The zero relative pronoun
1.5 Use with preposition
1.6 That and which
1.7 Summary
2 Special types and variants
2.1 Adverbial relative clauses
2.2 Gapless relative clauses
3 See also
4 References



[edit] Variables in the basic relative clause

[edit] Human or non-human
In their choice of relative pronoun, English-speakers will often distinguish between an antecedent that is a human—who(m)—and an antecedent which is a non-human—which. In this regard, English is unique among the Germanic languages; this distinction may be due to French influence, and is clearly related to the distinction between the interrogative words who(m) and which and that between the (s)he pronouns and it(s).

However, this distinction applies only to the which and who. The alternative that is found with both human and non-human antecedents. While some writers recommend reserving that for nonhuman antecedents, this does not reflect majority use. Examples can be found in Shakespeare (the man that hath no music in himself[1]), Mark Twain (The Man that Corrupted Hadleyburg), and Ira Gershwin (The Man that Got Away).

Although whose, as the possessive form of who, is often reserved for human antecedents, is commonly found also with nonhuman ones.


[edit] Restrictive or non-restrictive
Restrictiveness is more clearly marked in English than in most languages: prosody (in speaking) and punctuation (in writing) serve this purpose. An English non-restrictive relative clause is preceded by a pause in speech or a comma in writing, whereas a restrictive clause normally is not. Compare the following sentences, which have two quite different meanings, and correspondingly two clearly distinguished intonation patterns, depending on whether the commas are inserted:

(1) The builder, who erects very fine houses, will make a large profit.
(2) The builder who erects very fine houses will make a large profit.
The first example, with commas, and with three short intonation curves, contains a non-restrictive relative clause. It refers to a specific builder, and assumes we know which builder is intended. It tells us firstly about his houses, then about his profits. The second example uses a restrictive relative clause. Without the commas, and with a single intonation curve, the sentence states that any builder who builds such houses will make profits.

A distinction is also sometimes drawn between that (restrictive) and who / which (non-restrictive); see "That and which" below.

Restrictive relative clauses are also called defining relative clauses, or identifying relative clauses. Similarly, non-restrictive relative clauses are called non-defining or non-identifying relative clauses. For more information see restrictive clause and the relevant subsection of relative clause.


[edit] Grammatical case
In the Germanic languages, the case of a relative pronoun is generally marked in its form. In English, this survives only in who, which has a possessive case form whose and an objective case form whom. But the form whom is in decline and is now often restricted to formal use.

Since which and that have no possessive forms, whose is now also used for the possessive form of these, or periphrasis is sometimes employed:

There is an old house in our street, whose roof Jack fixed.
There is an old house in our street, the roof of which Jack fixed.

[edit] The zero relative pronoun
Further information: Reduced relative clause
English, unlike other West Germanic languages, has a zero relative pronoun. It is an alternative to that in a restrictive relative clause, except that it cannot be the subject of the clause's main verb. Example:

Jack built the house that I was born in.
Jack built the house Ø I was born in.
But only

Jack built the house that was sold yesterday.
and never

*Jack built the house Ø was sold yesterday.
Relative clauses headed by zeros are frequently called contact clauses in TEFL contexts. They are also often referred to as "zero clauses".

In cases where the relative clause is passive, the auxiliary verb (i.e., was) may also be removed,[2] sometimes yielding garden path sentences such as the following:

The horse raced past the barn fell.
which is derived from

The horse that was raced past the barn fell.

[edit] Use with preposition
In formal writing, a preposition in a relative clause appears together with the relative pronoun. In this case the pronoun must be either whom or which; never that, and since this is now formal usage, it would be unusual to use who.

Jack is the boy with whom Jenny fell in love.
Jack built the house in which I grew up.
However, in English it is also possible to leave the preposition where it would be if the clause were an independent clause. Though John Dryden raised in 1672 the issue that this preposition-stranding is not considered correct[citation needed], it was already in widespread use by that time, and now has wide usage among English speakers, especially in colloquial situations. Therefore, although a grammarian might insist upon the sentence, "Jack is the boy with whom Jenny fell in love", any of the following might be heard in ordinary speech:

Jack is the boy whom Jenny fell in love with.
Jack is the boy who Jenny fell in love with.
Jack is the boy that Jenny fell in love with.
Jack is the boy Jenny fell in love with.

[edit] That and which
The distinction between the relative pronouns that and which to introduce relative clauses with non-human antecedents, and that vs. who for human antecedents, is a frequent point of dispute. Of the two, only which is at all common in non-restrictive clauses.[3] The dispute mainly concerns restrictive clauses: in informal American speech and in formal and informal British English that or which are both commonly (and apparently randomly) used, but in formal American English it is generally recommended to use only that,[4] or to reduce to a zero clause. This rule was recommended in 1926 by H.W. Fowler, who observed, "Some there are who follow this principle now; but it would be idle to pretend that it is the practice either of most or of the best writers."[5] According to Stanford linguist Arnold Zwicky, "Most linguists—especially sociolinguists—think this a really silly idea."[6]


[edit] Summary
The most common distribution of the forms is therefore as follows (though variations may be heard).

Restrictive Nonrestrictive
Human Nonhuman Human Nonhuman
Subject who, that which, that who which
Object who, whom, that, Ø which, that, Ø who, whom which
After preposition whom which whom which
Possessive whose, of whom whose, of which whose, of whom whose, of which


[edit] Special types and variants
Nominal relative clauses English allows what is called a fused or nominal relative clause — a relative clause that does not modify an external noun phrase, and instead has a nominal function fused into it. For example:

What he did is clearly impossible, but I saw him do it.

Here, what he did has the sense of that which he did, i.e. the thing that he did, and functions as the subject of the verb is. Nominal relative clauses are inherently restrictive.

English has a number of fused relative pronouns, such as what, whatever, and whoever, but all can introduce other kinds of clauses as well; what can also introduce interrogative content clauses ("I do not know what he did"), for example, and both whatever and whoever can introduce adverbials ("Whatever he did, he does not deserve this").


[edit] Adverbial relative clauses
Much as a relative clause can modify a noun phrase, it can modify an entire clause. This makes sense when examined from a sentence-combination standpoint:

He designed a beautiful house. I plan to build it. → He designed a beautiful house, which I plan to build. (Modifying a noun phrase)
He designed a beautiful house. I think that is very impressive. → He designed a beautiful house, which I think is very impressive. (Modifying an entire clause). However, note that it in the first sentence is the act of designing that is thought impressive, and that it in the second sentence is the house that is.
Such a relative clause is called an adverbial relative clause. Only non-restrictive relative clauses can be used adverbially.


[edit] Gapless relative clauses
A relatively common phenomenon in speech, though generally seen as ungrammatical or bad style, is a sentence like the following:

Portman, who I wonder if she’ll ever better her role in Leon, is good here also, […][1]
The second message comes from a person who I don't know if the military is the right thing for them because they […][2]
Here the speaker appears to change in mid-track: having begun to utter a relative clause he realises that the pronoun can be neither its subject nor object, and attempts a repair "on the hoof". These sentences could be turned into standard relative clauses by omitting the intruding verbs of speech (Portman, who will never better […]; a person for whom the military is not […]), or the need for the relative could be eliminated by beginning with this verb (I wonder if Portman will […]; I don't know if the military is […]). In writing, most people would choose one of these alternatives, but in speech, the hybrid is not unusual. Leech et al. (1985) refer to these phenomena as "pushdown elements".