Adjective clauses, also known as relative clauses, are fundamental building blocks of complex sentences in English. They function like adjectives, modifying nouns or pronouns by providing additional descriptive information. Understanding and effectively using adjective clauses can significantly enhance the clarity, sophistication, and precision of your writing.
This guide will demystify adjective clauses, offering a comprehensive look at their structure, function, and common pitfalls. We will explore the various relative pronouns and adverbs that introduce these clauses, along with essential rules for punctuation and usage. Through clear explanations and practical examples, you’ll gain the confidence to master adjective clauses.
The Essence of Adjective Clauses
An adjective clause is a type of dependent clause that describes or identifies a noun or pronoun. It cannot stand alone as a complete sentence because it relies on an independent clause for its full meaning. These clauses always begin with a relative pronoun or a relative adverb.
The primary role of an adjective clause is to add detail. Without them, sentences might be shorter and more simplistic, lacking the richness that descriptive language provides. They answer questions about the noun, such as “Which one?” or “What kind?”
Consider the sentence: “The book is on the table.” This is a simple statement. Now, let’s add an adjective clause: “The book that I borrowed from the library is on the table.” The clause “that I borrowed from the library” tells us specifically which book we are talking about.
Relative Pronouns: The Gatekeepers of Adjective Clauses
Relative pronouns are words that introduce adjective clauses and also connect them to the noun or pronoun they modify. These pronouns serve a dual purpose: they act as a conjunction and a pronoun within the clause.
The most common relative pronouns are who, whom, whose, which, and that. Each has specific uses based on whether you are referring to people, animals, or things, and their grammatical role within the clause (subject, object, or possessive).
Understanding ‘Who’ and ‘Whom’
Who and whom are used exclusively for people. Who functions as the subject of the verb in the adjective clause. For example, “The artist who painted this masterpiece is world-renowned.” Here, “who” is the subject performing the action of “painted.”
Whom, on the other hand, functions as the object of the verb or the object of a preposition within the adjective clause. A helpful trick is to see if you can replace “who” or “whom” with “he/she” (for who) or “him/her” (for whom) in a rephrased version of the clause. “The student whom the teacher praised was very diligent.” If we rephrase the clause: “The teacher praised him.” Since “him” is an object pronoun, “whom” is correct.
Using whom correctly can be challenging, and in informal contexts, who is often used even when whom is technically correct. However, in formal writing, adhering to the distinction is important. “To whom it may concern” is a classic example where whom is used as the object of the preposition “to.”
The Versatility of ‘Which’
Which is used to refer to animals and things. It can function as the subject or object within the adjective clause. “The car which I bought last year is already in need of repair.” In this sentence, “which” is the object of the verb “bought.”
When referring to non-essential information, which is often preceded by a comma. This introduces a non-restrictive adjective clause, which provides extra, but not vital, information. “My brother, which is a doctor, lives in New York.” This sentence implies the speaker has only one brother.
The choice between that and which is often dictated by whether the clause is restrictive or non-restrictive. While that is generally preferred for restrictive clauses referring to things, which can also be used, especially in British English. However, it is crucial to remember that which is almost always used for non-restrictive clauses, typically set off by commas.
The Power of ‘That’
That is a highly versatile relative pronoun used for people, animals, and things. It is most commonly used in restrictive adjective clauses, meaning the clause is essential to identify the noun it modifies. “The house that Jack built is quite famous.” The clause “that Jack built” is necessary to know which house is being discussed.
Unlike who and which, that cannot be used to introduce non-restrictive clauses. You will never see a comma before that when it introduces an adjective clause. This is a key distinction in formal grammar. “My car, that is red, needs a wash.” This is grammatically incorrect; it should be “My car, which is red, needs a wash.”
In many cases, the relative pronoun (especially that, whom, and which when they are the object of the verb in the clause) can be omitted entirely. “The book (that) I am reading is fascinating.” The word “that” can be left out here without changing the meaning or grammatical correctness.
The Possessive ‘Whose’
Whose is the possessive relative pronoun, used for people, animals, and sometimes things, to indicate ownership or association. It functions similarly to possessive pronouns like “his,” “her,” or “its.” “The student whose project won first prize received a scholarship.” Here, “whose” shows that the project belongs to the student.
While traditionally used for people, the use of whose with inanimate objects is increasingly accepted, especially when it avoids awkward phrasing. For instance, “a building whose architecture is striking” is often preferred over “a building the architecture of which is striking.” This demonstrates a pragmatic evolution in language use.
Ensuring whose is used correctly prevents ambiguity. It clearly links the possessed item to its owner. “I met the woman whose dog bit me.” This is clear; without whose, the sentence would lack essential information about the dog’s connection to the woman.
Relative Adverbs: Expanding the Descriptive Horizon
In addition to relative pronouns, certain relative adverbs can also introduce adjective clauses. These adverbs typically refer to time, place, or reason.
The primary relative adverbs are when, where, and why. They function similarly to relative pronouns by connecting the dependent clause to the main clause and providing descriptive information about a noun, usually related to time, location, or cause.
‘When’ for Time
The relative adverb when introduces an adjective clause that modifies a noun referring to a specific time, day, or period. “I remember the day when we first met.” The clause “when we first met” describes the noun “day.”
This adverb can often replace phrases like “at which time” or “on which.” “The year when I graduated was particularly hot.” This is equivalent to “The year on which I graduated was particularly hot.” Using when makes the sentence more concise and natural.
It is important that when clearly modifies a noun indicating time. If the sentence structure doesn’t support this, using when might lead to confusion. “He arrived at the moment when the clock struck twelve.” The temporal connection is clear.
‘Where’ for Place
Where introduces an adjective clause that modifies a noun referring to a specific place or location. “This is the town where I grew up.” The clause “where I grew up” provides information about the noun “town.”
Similar to when, where can often replace phrases like “at which place” or “in which.” “The restaurant where we had dinner was excellent.” This means “The restaurant in which we had dinner was excellent.” The adverb streamlines the sentence.
One common error is using where when the antecedent is not a specific place. For example, “The situation where he felt lost was temporary.” Here, “situation” is not a physical place, so where is inappropriate; “in which” or a rephrased sentence would be better. “The situation in which he felt lost was temporary.”
‘Why’ for Reason
The relative adverb why introduces an adjective clause that modifies a noun referring to a reason or explanation. “I don’t understand the reason why he left.” The clause “why he left” explains the noun “reason.”
Often, the noun “reason” is implied rather than stated. In such cases, why can directly follow the verb or noun it relates to. “The reason why she succeeded is her dedication.” This is a standard construction.
It’s also common to see the word “reason” and “why” used together, which is grammatically redundant. “The reason why he was late…” is less preferred than “The reason that he was late…” or simply “Why he was late…” or “The reason for his lateness…”. The most elegant form is often omitting “reason” and using “that” or omitting the relative pronoun altogether if it’s an object. “The reason that he left is unclear.” Or more simply, “Why he left is unclear.”
Restrictive vs. Non-Restrictive Adjective Clauses
A crucial distinction in using adjective clauses lies between restrictive and non-restrictive types. This difference impacts both meaning and punctuation.
Restrictive clauses are essential to the meaning of the sentence. They identify or specify the noun they modify, narrowing down its identity from a broader category. If you remove a restrictive clause, the core meaning of the sentence changes significantly, or the sentence becomes unclear about which specific noun is being referred to.
These clauses are never set off by commas. The relative pronouns used are typically that (preferred for things and people) or who/which (when that isn’t suitable or for stylistic reasons). “The student who scored highest on the exam received an award.” Without the clause, we wouldn’t know which student received the award.
Non-restrictive clauses, conversely, provide additional, non-essential information about a noun that is already clearly identified. They add descriptive detail but are not necessary to identify the noun. Removing a non-restrictive clause does not alter the fundamental meaning of the sentence.
Non-restrictive clauses are always set off by commas. If the clause appears in the middle of a sentence, it is usually preceded and followed by a comma. The relative pronouns used are typically who, whom, whose, and which. That is generally not used in non-restrictive clauses. “My sister, who lives in London, is visiting next week.” The identity of “my sister” is already specific; the clause adds extra information about her.
Consider the difference: “The employee who completed the training will receive a bonus.” This implies there are multiple employees, and only the one who completed the training gets the bonus (restrictive). However, “The employee, who completed the training, will receive a bonus,” suggests there is only one employee, and the fact that they completed the training is just extra information.
The choice between restrictive and non-restrictive usage depends entirely on the intended meaning. If the clause is needed to identify the noun, it’s restrictive and takes no commas. If the noun is already specific and the clause adds extra detail, it’s non-restrictive and requires commas.
Punctuation Rules for Adjective Clauses
Correct punctuation is vital for clarity when using adjective clauses. The presence or absence of commas signals whether the clause is restrictive or non-restrictive.
As previously stated, restrictive adjective clauses are essential for identifying the noun and are therefore not set off by commas. The clause is integrated directly into the sentence’s core meaning. “The car that is parked illegally will be towed.” The clause specifies which car.
Non-restrictive adjective clauses, providing supplementary information, are always enclosed by commas. If the clause appears at the end of a sentence, it is preceded by a single comma. “I spoke to John, who is my neighbor.” The clause adds information about John, who is already identified.
If a non-restrictive clause interrupts the flow of the main clause, it is set off by two commas. “The Eiffel Tower, which is a famous landmark, is located in Paris.” The descriptive phrase is additional detail about an already specific landmark.
Be mindful of the relative pronoun used. Generally, that introduces restrictive clauses and is not preceded by a comma. Who, whom, whose, and which can introduce both restrictive and non-restrictive clauses, depending on whether commas are used.
When an adjective clause is introduced by a preposition, the preposition usually stays with the relative pronoun. For non-restrictive clauses, the preposition precedes the relative pronoun and is followed by a comma. “The house in which I grew up is still standing.” (Restrictive) vs. “My childhood home, in which I have many memories, is being sold.” (Non-restrictive).
Omitting Relative Pronouns
In certain circumstances, the relative pronoun in an adjective clause can be omitted. This makes sentences more concise and fluid, particularly in spoken English and less formal writing.
The relative pronoun can be omitted when it functions as the object of the verb or the object of a preposition within the adjective clause. It cannot be omitted when it acts as the subject of the verb in the clause. “The movie (that) we watched last night was excellent.” Here, “that” is the object of “watched” and can be omitted.
Consider this example: “The person (whom) I met was very helpful.” “Whom” is the object of “met,” so it can be omitted. However, in “The person who helped me was very kind,” “who” is the subject of “helped,” so it cannot be omitted.
When the relative pronoun is the object of a preposition, the preposition can either precede the pronoun (in formal English) or follow the verb (in less formal English, allowing omission of the pronoun). “This is the book about which I was telling you.” (Formal) vs. “This is the book that I was telling you about.” (Less formal, with omitted pronoun possible: “This is the book I was telling you about.”).
Common Errors and How to Avoid Them
Mastering adjective clauses involves recognizing and correcting common grammatical errors. Attention to detail can prevent misunderstandings and improve writing quality.
One frequent mistake is the misuse of who versus whom. Remember, who is a subject pronoun (like he, she, they) and whom is an object pronoun (like him, her, them). Test by substituting: if “he/she” fits, use who; if “him/her” fits, use whom.
Another common error is the incorrect use of commas with restrictive and non-restrictive clauses. Always double-check if the clause is essential for identification. If it is, no commas. If it’s extra information, use commas.
Confusing that and which is also prevalent. Generally, use that for restrictive clauses (no commas) and which for non-restrictive clauses (with commas). While there are nuances, this is a solid guideline for most situations.
Avoid dangling modifiers. This occurs when an adjective clause seems to modify a word that isn’t actually present or clearly stated in the sentence. For example, “Walking down the street, the tall building came into view.” It sounds like the building was walking. A corrected version: “Walking down the street, I saw the tall building.”
Ensure your relative pronoun clearly refers to a specific noun or pronoun. Ambiguous antecedents can lead to confusion. “The teacher told the student he was late.” Who was late, the teacher or the student? Rephrase for clarity: “The teacher told the student, ‘You are late.'” or “The teacher informed the student that the student was late.”
Practice Exercises
Applying these rules through practice is the most effective way to solidify your understanding of adjective clauses.
Exercise 1: Identify the Adjective Clause and the Word it Modifies.
1. The dog that barked all night finally fell asleep.
2. I enjoyed the book which you recommended.
3. The woman whose car was stolen reported it to the police.
4. This is the park where we used to play.
5. She explained the reason why she was upset.
Exercise 2: Determine if the Clause is Restrictive or Non-Restrictive and Add Commas if Necessary.
1. My brother who is a lawyer lives in Chicago.
2. Mount Everest which is the world’s highest peak attracts many climbers.
3. The car that I bought needs a new paint job.
4. My favorite restaurant which serves Italian food is closed today.
5. The students who passed the exam celebrated.
Exercise 3: Rewrite the Sentences, Omitting the Relative Pronoun Where Possible.
1. The song that I heard on the radio was catchy.
2. The package that was delivered this morning is for you.
3. I met the artist whose paintings are displayed here.
4. The film that we saw last night was very moving.
5. This is the chair on which I like to sit.
Exercise 4: Correct the Errors in the Following Sentences.
1. Who did you give the keys to?
2. The house that is on the corner, is haunted.
3. I don’t know why is he late.
4. The manager, who was very busy, couldn’t see me.
5. I saw the dog chasing it’s tail.
By actively engaging with these exercises, you will begin to internalize the patterns and rules governing adjective clauses, leading to more confident and accurate sentence construction.
Advanced Usage: Combining Clauses and Avoiding Redundancy
Beyond basic identification and punctuation, skilled writers often combine multiple adjective clauses or employ them strategically to create nuanced meaning. This requires a keen eye for conciseness and clarity.
When multiple descriptive details are needed, two or more adjective clauses can modify the same noun. For instance, “The scientist who discovered the cure and whose research was groundbreaking received international acclaim.” This sentence uses two restrictive clauses to precisely identify the scientist.
Be cautious of creating sentences that become overly long or convoluted with too many stacked clauses. If a sentence feels cumbersome, consider breaking it into two or more simpler sentences or rephrasing to use other grammatical structures.
Another aspect of advanced usage is avoiding redundancy. Phrases like “the reason why” or “the place where” can sometimes be shortened. “The reason why he left” can often be improved to “the reason that he left,” “why he left,” or “his reason for leaving.” Similarly, “the place where we met” can become “the place we met” or “where we met.”
The goal is to convey information effectively and elegantly. While strict adherence to rules is important, understanding the spirit of concise communication allows for more natural and impactful writing. Always ask yourself if there’s a simpler, clearer way to express the same idea.