1. Relative clauses are “embedded” grammatical structures, contained inside other grammatical structures.
2. Relative clauses play a central role in English discourse.
3. Relative clause knowledge is important for reading comprehension and written expression.
4. Relative clauses can be confused with other similar-looking grammatical structures.
5. There are different types of relative clauses with different properties.
6. Some relative clauses contain “gaps,” where it looks like a sentence element is missing.
7. Relative clauses pose a considerable challenge for deaf students.
8. Deaf students have a better command of some relative clause types than other types.
9. Sentences containing relative clauses can be simplified to make English texts and tests more accessible to deaf students.
10. Course materials can be structured to enhance students’ knowledge of English relative clauses.
A relative clause is a grammatical structure that is “embedded” somewhere inside a sentence. The relative clause cannot stand on its own. Instead, it is contained by another sentence constituent, usually a noun phrase. Like all clauses, a relative clause must have at least a subject and a verb and may have an object and other grammatical phrases as well.
In the following sentence the underlined relative clause has a subject (which), a verb (has), and an object (a solid state image sensor).
A camera which has a solid-state image sensor is a digital camera.
The relative clause is contained inside the main clause portion, A camera… is a digital camera. Specifically, it is contained inside the noun phrase a camera to form a larger noun phrase, a camera which has a solid-state image sensor.
The grammatical function of the relative clause is to “modify” the noun phrase that contains it. In other
words, it describes or limits the meaning of the noun phrase.
Restrictive Relative Clauses
For example, in the sentence
A camera which has a solid-state image sensor is a digital camera.
the relative clause limits the noun phrase a camera to the specific kind of camera described by the information in the relative clause. Without that information, the sentence has an entirely different meaning. Compare the sentence below, without a modifying relative clause, with the one above:
A camera is a digital camera.
This sentence implies that all cameras are digital cameras, which is not true. The relative clause in the first sentence describes a very specific kind of camera. Its content is crucial to the meaning of the sentence. In grammatical terms, this kind of relative clause is known as a “restrictive” relative clause because the relative clause “restricts” or limits the meaning of a noun phrase in some way.
Nonrestrictive Relative Clauses
A second kind of relative clause is known as a “nonrestrictive” (or “appositive”) relative clause. Instead of restricting the meaning of a noun phrase, the nonrestrictive relative clause simply provides extra information about a noun phrase. In the sentence
Adobe Photoshop, which is a photo-editing software program, can be purchased at the bookstore.
the nonrestrictive relative clause explains what Adobe Photoshop is. It does not limit the meaning of Adobe Photoshop in any way. Without the relative clause the sentence is still true: Adobe Photoshop can be purchased at the bookstore.
Commas with Nonrestrictive Relative Clauses
In addition to the important meaning differences associated with restrictive and nonrestrictive relative clauses, notice that it is only the nonrestrictive relative clause that is surrounded by commas in written English. In the following sentence, the restrictive relative clause who use digital cameras is contained inside the nonrestrictive relative clause, which now hire adjusters. The nonrestrictive relative clause provides elaboration on the noun phrase insurance companies, and the restrictive relative clause limits the noun phrase adjusters to only those who use digital cameras.
Insurance companies, which now hire adjusters who use digital cameras, can complete estimates much faster than in the past.
Relative Clauses in Discourse
In addition to their roles inside sentences, relative clauses play an important role in “discourse.” Discourse refers to a sequence of sentences that make up a message, a story, or a text. Sentences with relative clauses help to keep information flowing. They introduce a new topic or set the stage for the development of a topic. They help to compare different kinds of items. They provide elaboration or background information about a noun phrase. And they can refer back to earlier information in the discourse.
Introducers that and wh-Words and Phrases
A relative clause can begin with one of the following kinds of relative clause “introducer”:
1. the word that
2. a “wh-word” such as who, whom, or which
3. a “wh-phrase” that begins with whose or that includes one of the wh-words in #2.
Examples of #3 are whose camera, to whom, and from which. The following sample sentences illustrate these options:
A scanner is a device that allows you to convert an image to a digital format.
A scanner is a device which allows you to convert an image to a digital format.
A scanner is a device with which you can convert an image to a digital format.
A scanner is a device that allows you to convert an image to a digital format.
The photographer whose scanner I borrowed asked me to return it.
The photographer from whom I borrowed a scanner asked me to return it.
The photographer who I borrowed a scanner from asked me to return it.
The photographer that I borrowed a scanner from asked me to return it.
No Introducer
A fourth option for introducing a relative clause involves neither that nor a wh-word or phrase. In such cases, the relative clause has no introducer as in the sentences below.
The photographer I borrowed a scanner from asked me to return it.
There are many things you can do with a digital camera.
Other Function of that
A problem with identifying English relative clauses is that the same words that serve as relative clause introducers have other functions. The word that is used as a “demonstrative pronoun” as in that book or I find that interesting. The word that is also used to introduce “that-clauses” (sometimes called “noun clauses”) as in the sentence below.
The photographer said that the image should be enlarged.
Wh-Words/Phrases in Other Embedded Structures
In addition to introducing relative clauses, wh-words and phrases are used to introduce various kinds of embedded sentence structures as in the following sentences:
The professor asked who was interested in digital photography.
The students were arguing about whose camera should be used for the project.
Unlike relative clauses, that-clauses and these embedded wh-clauses occur in positions that regular noun phrase objects can occur in. Compare the above three sentences with the following three sentences:
The photographer said something.
The professor asked a question.
The students were arguing about a decision.
A relative clause, on the other hand, occurs inside a noun phrase and modifies the noun that it immediately follows.
Of course, another function of wh-words and phrases is that they are used in “wh-questions” as in the following examples:
Who did you buy that scanner from?
From whom did you buy a scanner?
Which scanner did you buy?
Whose scanner did you buy?
One of the most distinguishing characteristics of English relative clauses is that they often contain “gaps.” A gap is a position within a sentence structure where something appears to be missing in comparison with most other typical sentence structures. In an ordinary main clause or an independent sentence, the major grammatical phrases generally appear in the order:
Subject Verb Object
In contrast, in a relative clause there will be a gap when the targeted grammatical phrase would appear in any position other than the subject position.
Subject Position
First consider relative clauses that target the subject position:
The photographer who lent me a scanner asked me to return it.
In the relative clause, who appears in the subject position before the verb lent, so there is no gap.
Object Position
However, in the next sentence, who represents the object position after visited, so there is a gap in that position (represented for the sake of illustration by a “bullet”).
The photographer who I visited • at the lab lent me a scanner.
Comparing that relative clause with a sentence like I visited the photographer shows that a noun phrase object ordinarily appears in the object position after the verb visited.
Object of Preposition Position
In the next two sentences, the gap appears after the preposition from. Compare I borrowed a scanner from the photographer.
The photographer who I borrowed a scanner from • asked me to return it.
The photographer that I borrowed a scanner from • asked me to return it.
Wh-Phrase with Whose
In the sentence below, the gap occurs after borrowed and represents the entire wh-phrase whose scanner, which has “moved up” to the front of the relative clause. Compare I borrowed her scanner.
The photographer whose scanner I borrowed • asked me to return it.
Entire Wh-Phrase Starts Relative Clause
Similarly, the gap in the next sentence occurs after a scanner and represents the entire prepositional phrase from whom, which has moved up to the front of the clause. Compare I borrowed a scanner from him.
The photographer from whom I borrowed a scanner • asked me to return it.
Gap Can Be Far Away
In more complex sentences that contain a variety of embedded clauses within the relative clause itself, the gap can be very far away from the front of the relative clause. Note the positions of the gaps in the following sentences.
The photographer that my teacher recommended that I borrow a scanner from • refused to lend one to me.
A technique which we were advised to consider using • for our project yielded successful results.
The software my friend told me her brother thought we should buy • through a mail order catalogue was out of stock.
Head of Relative Clause and Relativized Position
In grammatical terms, the noun phrase modified by the relative clause is sometimes called “the head noun phrase” or “the head” of the relative clause. And the targeted position within the relative clause (the subject position or the gap) is called the “relativized position.” Using these terms will facilitate the discussion of research associated with the acquisition of English relative clauses.
Research on the acquisition of English relative clauses has often focused on the relationship between the head noun phrase of the relative clause and the relativized position within the relative clause. For example, is the head noun phrase the subject or the object within the main clause, and is the relativized position the subject or the object within the relative clause. If we focus only on these positions, there are four kinds of sentences containing relative clauses:
Four Sentence Types
The sentences below illustrate the four sentence types:
In the SS sentence, for example, the employer is the subject of the main clause, and who represents the subject of the relative clause. In the OO sentence the lawyer is the object of visited within the main clause, and the gap within the relative clause represents the object of hired.
Deaf Students’ Knowledge of Four Sentence Types
With respect deaf students’ knowledge of such relative clause sentences, results are mixed.Quigley, Smith, and Wilbur (1974) found that deaf children and adolescents generally had greater knowledge of OS and OO relative clause sentences than of SS and SO sentences. In another study, de Villiers (1988) found that deaf children performed the best on SS sentences and not very well on the other types. The two studies used different methodologies and focused on deaf students with different characteristics, which might explain the contradictory results.
At the college level, Lillo-Martin, Hanson, and Smith (1992) got results that were similar to the results of Quigley, Smith, and Wilbur (1974). That is, deaf college students had better knowledge of OS and OO relatives. In a study of deaf college students’ production of English relative clauses, Berent (2000) found that the vast majority of relative clause sentences produced by the students were OS and OO relatives. From these studies, most of the evidence suggests the following:
Deaf students have greater knowledge of OS and OO relative clause sentences than SS and SO sentences.
“Right-Branching” and “Center-Embedded” Relative Clauses
The most likely reason for this greater knowledge of OS and OO sentences is that, in these sentence types, the relative clause “branches to the right of the main clause.” Therefore, the relative clause does not “interrupt” the SUBJECT-VERB OBJECT constituents of the main clause.
In contrast, in SS and SO sentences, the relative clause falls right in the center of the main clause and interrupts the main clause constituents. As noted in Berent (1988), an SO sentence will have the following sequence of major constituents, including wh-words but ignoring gaps:
However, an OS sentence will have the following sequence:
Apparently, the OS ordering is easier to process that the SO ordering, with its adjacent subjects and adjacent verbs.
With respect to SS sentences, Quigley and King (1980) noted that deaf students often misinterpret the subject of the action expressed by the relative clause. For example, in the SS sentence above (The employer who visited the lawyer hired the photographer.), some students might interpret the sentence to mean, in part, that the lawyer hired the photographer. This might happen because the lawyer is followed immediately by hired. Therefore, to some students the lawyer looks like the subject of hired.
Deaf Students’ Knowledge of Three Relativized Positions
Berent (1990) , summarized in Berent (1996a) , examined deaf college students’ knowledge of relative clauses in which three different positions were relativized—the subject (SUBJ), the object of the verb (OBJ), and the object of a preposition (OBJ/PREP). In all of the sentence types, the relative clauses branched to the right of the main clause. The three relative clause types are illustrated in the following sentences, with gaps represented by “bullets”:
SUBJ: Louise likes the photographer who explained the answer to the visitor .
OBJ: Jack knows the employer who the photographer met • in the office .
OBJ/PREP: Kathy misses the advisor who the student got the information from • .
The deaf college students were very successful in both producing SUBJ sentences and in judging them as grammatical English sentences. They were very unsuccessful in both producing and judging the other two sentence types, although they were slightly better on OBJ sentences than on OBJ/PREP sentences.
Deaf Students’ Knowledge of Three Positions with whose
On parallel sentences involving whose , illustrated below, production was much worse. Again, the students were most successful on SUBJ sentences. However, they produced hardly any OBJ or OBJ/PREP sentences correctly. In judging the grammatical status of the three sentence types with whose , the students were very successful on SUBJ sentences, but not very successful at all on the other two types.
SUBJ: Louise likes the photographer whose assistant explained the answer to the visitor .
OBJ: Jack knows the employer whose secretary the photographer met • in the office .
OBJ/PREP: Kathy misses the advisor whose colleague the student got the information from • .
The results of this study indicate the following with respect to relative clauses that branch to the right of main clauses:
Deaf college students are most successful on sentences in which the relativized position is the subject. They are not very successful on the object position and even less successful on object of preposition position. Except for relativized subject position, they are not very successful at all on relative clauses containing whose .
Deaf Students’ Production of Relative Clauses
In a study of deaf college students’ spontaneous written production of English relative clauses, Berent (2000) found that deaf students rarely used wh -words and phrases in their relative clauses, with the exception of who in the subject position:
The photographer who lent me a scanner asked me to return it.
With respect to the use of the word that as a relative clause introducer, they mostly used that to introduce relative clauses targeting subject and object position within the relative clause:
A scanner is a device that converts an image to a digital format .
A scanner is a device that you can buy • at a computer store .
They also often introduced relative clauses targeting object position without using that or a wh -word:
A scanner is a device you can buy • at a computer store .
The students almost never produced relative clauses in which the relativized position was the object of preposition position or a more deeply embedded position, and they produced no relative clauses beginning with a preposition followed by a wh -word as in
The photographer from whom I borrowed a scanner asked me to return it.