"That" in non-defining relative clauses

Hi, OverlyCurious.  Generally speaking, the relative pronoun ‘’that" is not used in non-restrictive clauses. This is a rule, born of the inductive method after examining a large number of sentences from native speakers, and not prescribed by authoritative grammarians, therefore, we must abide by it,  and there is no reason behind it, if we'd like to write or say the correct English.  Of course, there is every now and then an exception to the rule.  I cannot guarantee it covers all.

Hi, OverlyCurious,

The rule says that you cannot use "that" in non-defining or non-restrictive clauses, but you can use "which" or "who" instead:

- This is an important rule, which you must remember at all times.
- OverlyCurious, who is a GE member, is interested in the rules that/which apply to the use of relative pronouns.

@OverlyCurious posted:

. . . I don't understand why I can't use "that" in non-defining relative clauses.

Hi, everybody—I'd like to add a couple points to this good discussion on a very interesting topic. First, although it is indeed a rule in modern English that "that" cannot introduce nonrestrictive relative clauses, this was not a rule in Early Modern English or in Middle English.

We can find nonrestrictive relative clauses beginning with "that" in Shakespeare, in the writings of John Milton, and even in the King James translation of the Bible. Below is an excerpt from a poem by Andrew Marvell (1621-1678) titled "The Coronet." The highlighted "that"s introduce nonrestrictive clauses:

"Alas, I find the serpent old

That, twining in his speckled breast,

About the flowers disguised does fold,

With wreaths of fame and interest.

Ah, foolish man, that wouldst debase with them,

And mortal glory, Heaven’s diadem!"

Second, I can give at least one good reason for the Modern English rule proscribing using "that" in this way. If "that" introduced a nonrestrictive relative clause in which the relative pronoun functions as subject, the "that" would, at least in many cases, be indifferentiable from the demonstrative pronoun "that," so that one would be unable to tell whether one were reading a run-on sentence, or a sentence containing a nonrestrictive relative clause. E.g.:

(1) I like the song "Titanium," that sounds really cool.

Sentence (1) can be parsed in two ways. On one interpretation, it is a run-on sentence, equivalent to this: "I like the song 'Titatium.' That sounds really cool." On the other interpretation, it is not a run-on sentence but is instead equivalent to this: "I like the song 'Titanium," which sounds really cool." Although the meaning is the same on both interpretations, the syntactic relationships are markedly different. The modern rule about "that" guards against this issue.

@f6pafd posted:

Hi, OverlyCurious.  Generally speaking, the relative pronoun is not used in non-restrictive clauses. This is a rule, born of the inductive method after examining a large number of sentences from native speakers, and not prescribed by authoritative grammarians, therefore, we must abide by it,  and there is no reason behind it, if we'd like to write or say the correct English.  Of course, there is every now and then an exception to the rule.  I cannot guarantee it covers all.

Thank you!

@Gustavo, Co-Moderator posted:

Hi, OverlyCurious,

The rule says that you cannot use "that" in non-defining or non-restrictive clauses, but you can use "which" or "who" instead:

- This is an important rule, which you must remember at all times.
- OverlyCurious, who is a GE member, is interested in the rules that/which apply to the use of relative pronouns.

Thank you!

@David, Moderator posted:

Hi, everybody—I'd like to add a couple points to this good discussion on a very interesting topic. First, although it is indeed a rule in modern English that "that" cannot introduce nonrestrictive relative clauses, this was not a rule in Early Modern English or in Middle English.

We can find nonrestrictive relative clauses beginning with "that" in Shakespeare, in the writings of John Milton, and even in the King James translation of the Bible. Below is an excerpt from a poem by Andrew Marvell (1621-1678) titled "The Coronet." The highlighted "that"s introduce nonrestrictive clauses:

"Alas, I find the serpent old

That, twining in his speckled breast,

About the flowers disguised does fold,

With wreaths of fame and interest.

Ah, foolish man, that wouldst debase with them,

And mortal glory, Heaven’s diadem!"

Second, I can give at least one good reason for the Modern English rule proscribing using "that" in this way. If "that" introduced a nonrestrictive relative clause in which the relative pronoun functions as subject, the "that" would, at least in many cases, be indifferentiable from the demonstrative pronoun "that," so that one would be unable to tell whether one were reading a run-on sentence, or a sentence containing a nonrestrictive relative clause. E.g.:

(1) I like the song "Titanium," that sounds really cool.

Sentence (1) can be parsed in two ways. On one interpretation, it is a run-on sentence, equivalent to this: "I like the song 'Titatium.' That sounds really cool." On the other interpretation, it is not a run-on sentence but is instead equivalent to this: "I like the song 'Titanium," which sounds really cool." Although the meaning is the same on both interpretations, the syntactic relationships are markedly different. The modern rule about "that" guards against this issue.

Very interesting information here, thank you for your answer!! I understand!