Defining Relative Clauses

Who is the usual choice for people, and which for things and concepts; in a defining relative clause, that can replace either. For animals, use which or that; who is also used for pets.

In these patterns, do not use which with ordinary nouns referring to people, or who with an inanimate object unless it is personified. The choice depends on what the word means in the situation, not just how it is written.

In this standard pattern, what does not serve as a relative pronoun after a noun. Do not transfer a translation of ‘what’ from other constructions into this one.

For clarity, put the clause close to the whole noun phrase it describes. It does not necessarily follow the noun itself immediately: the people in the office who speak Polish. If several nearby nouns are possible antecedents, rephrase the sentence to make the connection unambiguous.

As a result, a relative clause often interrupts the main clause: first the subject, then the relative clause, and only then the main verb. The important point is to remember to complete the main clause with its verb after the relative clause.

When the relative clause describes an object, it naturally occurs at the end of the sentence.

When who/which/that itself acts as the subject, the verb agrees with the noun being described. With an ordinary verb in the Present Simple: a colleague who speaks, colleagues who speak. This does not mean that every tense or modal verb requires -s.

A different noun is often nearby, which can be misleading. The verb in the relative clause agrees with the noun the clause refers to, not simply with the nearest word.

Because the relative pronoun already supplies the subject, do not add another pronoun to repeat that same subject inside the clause.

If a new subject such as I, she, my sister or our team follows who/which/that, the relative pronoun acts as the object of the clause. Someone else performs the action, and the noun from the main clause receives that action.

Word order inside the clause remains normal: subject, then verb. Do not repeat the object after the verb, because the relative pronoun at the beginning already represents it.

In defining relative clauses referring to people, modern standard English also accepts who as an object. Whom belongs to a more formal register and is not practised here.

Who/which/that already occupies the subject or object position in the relative clause. Adding he, she or it in that same role expresses the role twice and makes the sentence ungrammatical in this standard pattern.

This does not mean that every it in the sentence is unnecessary: the error is repeating a role inside the same relative clause. A pronoun belonging to the main clause stays in place.

Do not separate a defining relative clause with commas. Commas present a clause as an additional comment and change the message. The distinction between defining and non-defining clauses is a separate topic; here, keep defining relative clauses free of separating commas.

This rule covers only who, which and that. Expressing place, time and possession with where, when and whose, placing prepositions in relative clauses, omitting the relative pronoun, and using commas to change meaning are separate topics in the same section.

In everyday speech, defining relative clauses are especially useful when you need to specify exactly who or what you mean: in a complaint, when describing a lost object, or when recommending someone whose name you do not know. The clause then acts like a temporary name.

That is often preferred after all, everything, something, anything and superlatives. This is a useful usage preference, not a universal ban on which. At this stage, focus on confidently building natural examples with that.

Where can introduce a description of the place where an action happens: rooms, streets, cities, or shelves. Do not repeat the same place with an unnecessary there or in it. Another place with a different role may remain in the sentence.

Where replaces a preposition + which combination: “the shelf on which I keep the tools” and “the shelf where I keep the tools” describe the same shelf. That is why both markers are not used together—one of them would be unnecessary.

Bare which cannot perform this role: if the place inside the clause needs a preposition, you cannot begin the clause with which alone—you need where or a preposition + which combination. It is different when which is the object of a verb (“the village which we visited”): that is a construction from a neighboring rule, not an error.

When opens a clause after a noun that names a time: day, week, month, year, evening, moment, season. This is not the question word “when?”—it specifies which particular period is meant.

After a noun referring to time, English also allows two other ways to say the same thing: that instead of when, or nothing at all. In this lesson, we deliberately practise when, but the version with that is also correct, and the exercises accept it.

It is important not to use where for time: place and time are not interchangeable here.

In this pattern, whose comes before a noun phrase and replaces a possessive word: whose car, whose new car, whose mother. It shows possession or another connection, such as a family relationship; a mother is not anyone’s property.

Do not use an article between whose and this noun: whose the car is not possible. Do not use a possessive pronoun either—whose his van turns one possessive relationship into two.

Whose can refer to a person, organization, animal, or thing. In whose cover, it refers to part of an object, not literal ownership. The structure of the noun phrase is the same.

Who's is a short form of who is or who has, so the sentence already contains a subject and a verb. Whose does not shorten anything: it is a possessive word and must be followed by a noun.

Try expanding who’s to who is or who has and check the whole sentence. The guide who’s a musician correctly means “the guide who is a musician”; the guide whose group … shows the connection between the guide and the group. The presence of one noun after the form does not by itself decide the choice.

The same trap occurs with which: which does not show possession. The clause “the hotel which roof” is impossible; you need “the hotel whose roof”.

Do not add a second relative marker for the same role: the flat where which we live contains an unnecessary which. But words appearing next to each other are not automatically an error: the place where that man lives is correct because that here means “that” before man.

Do not duplicate the same role: where we live there contains an unnecessary there for the same place; whose his van has two possessive determiners. Another word with its own role may remain: the room where there is a desk—“the room where there is a desk”.

After where/when, there is usually a separate subject and verb. The whose + noun group itself can be the subject (whose van broke down) or the object before a separate subject (whose report we read).

These three words let you describe something by a feature rather than by its name: if you do not remember the name of a café, you can identify it by what happened there; if you do not know someone’s name, you can describe the person by what belongs to them.

The practical thought process is short: first name the noun, then ask yourself what exactly you are specifying about it—place, time, or possession—and only then open the clause.

In conversation, such clauses most often appear in advice, complaints, clarifying questions, and explanations of choices. They make speech more precise without requiring long separate sentences.

This lesson deals only with defining clauses—clauses that narrow the group and are written without commas. Clauses set off by commas add extra information and follow their own rule.

The basic choice among who, which, and that, the complete omission of the relative word, and versions with a preposition inside the clause belong to neighboring topic rules. They are mentioned here only for contrast, and none of them is presented as an error.

Interrogative whose is a different construction: in the question “Whose bag is this?” there is no noun before it for a clause to attach to. In this lesson, whose always has a possessor to its left.

Find the subject of the relative clause itself. If who/which/that is that subject, retain it: the neighbour who often calls. If a subject is already present and the relative word is an object, you can normally omit it: the neighbour (who) I called. An intervening adverb does not change these roles.

The new subject need not be a pronoun. It can be a whole noun phrase: my flatmate, the finance department, Marta. Looking only for I, we, or you can make you miss a subject that is already there.

The noun being described can be either a subject or an object in the main clause; this does not affect the rule. Only the role of who/which/that inside its own relative clause matters.

If the relative word is the clause's subject, it is the only element showing who performs the action. Omitting it leaves the verb without a subject.

The error creates two predicates without the required connection. A reader may initially interpret the beginning as a simple sentence, then have to return to the start.

This applies to both people and things: who, which, and that behave alike in the subject role. Here, the choice is between who/that for people or which/that for things, not between retaining and omitting the word.

When the relative word is omitted, its object position inside the clause must remain empty. Adding it, them, or him is a common mistake: the object is already identified by the noun before the clause.

The same restriction applies when the relative word is retained: in The parcel that we collected it, it is redundant, not that. Repeating the object is a separate error, independent of whether the relative word is included.

Reconstruct the simple statement: We collected the parcel. In the relative construction, parcel is already named before we collected, so do not repeat it with it. Check the object's role rather than whether the verb can ever occur without an object in other contexts.

Whose cannot be omitted under this rule: it expresses possession, and removing it also removes the relationship between the two nouns.

Do not mechanically apply the object who/which/that rule to where. For a place, check the required construction: the house where we live → the house we live in. Some phrases also allow a zero form, such as the place we live; that separate use does not make arbitrary omission of where safe.

In a relative clause set off by commas, the relative word is required even when it is an object. The commas show that the clause merely adds information instead of identifying the noun; such a clause does not allow omission.

Both versions are correct, but they are not always equally easy to read. If the relative clause's subject is long, that helps the reader immediately locate the clause's beginning.

The word is more often retained in an official letter, report, or instruction; it is commonly omitted in conversation and short messages. This concerns rhythm and clarity rather than correctness.

For people in the object role, who and that are both natural, and either can be omitted. Whom belongs to a markedly formal style and is unnecessary at this level.

Relative clauses without an object marker are very common in conversation. Look for a noun followed by a clause with its own subject: the book you read. Not every pair of adjacent nouns forms this construction.

When speaking, build the phrase in two steps: name the thing or person, then immediately add who did something involving them. No pause is needed between the parts, and you can leave out the relative word.

Questions work the same way. Clarifications such as the one you… commonly omit the relative word, providing a quick way to check exactly what someone means.

In everyday language, the preposition often stays after the verb: the person who I spoke to; the device which I work with. In a defining relative clause, an object relative pronoun can also be omitted. Who or which depends on what the preceding noun refers to.

The end of the clause is not always the end of the sentence. If the main predicate follows the relative clause, the preposition comes before it, rather than at the very end of the whole sentence.

This position is neutral. It is neither careless nor incorrect, and is the natural default in many situations. Moving the preposition forward is a deliberate stylistic choice.

In formal writing, such as a report, official letter, contract or covering note, a preposition can be moved to the start of the relative clause, immediately before the pronoun. This position has stricter requirements than the everyday pattern.

In this lesson's basic patterns, use preposition + whom for a person and preposition + which for a thing. These are not all possible constructions: in whose house is also correct, but whose with a noun has a different, possessive role.

Moving the preposition forward is not compulsory. The everyday version can also be correct in formal writing. Once you do move it, however, the remaining requirements of this pattern apply, and the pronoun choice is no longer free.

In the standard formal pattern, a fronted preposition requires an expressed whom or which: with whom, on which. Do not use relative that in this position or omit the relative pronoun.

Relative that cannot directly follow the fronted preposition: the desk on that I work is incorrect. This does not ban every sequence on that: in on that desk, that is a demonstrative determiner with a different role.

For a formal relative clause about a person, choose whom after the preposition. In the conversational pattern with the preposition at the end, who is usual: the person who I spoke to. This lesson targets that distinction between styles.

Some prepositions belong to established verb or adjective combinations: depend on, apply for, be responsible for. Others express the required location or direction: work in a room; work on a roof. Check both the word combination and the meaning you want to preserve.

Prepositions do not map mechanically between languages. English uses look at, wait for and explain to somebody, whereas marry someone has no preposition in this pattern. Learn the English combination rather than copying a source-language preposition.

First establish which preposition the English construction requires, then decide where to place it. Choosing a position cannot repair the wrong preposition.

Another common error is adding a second object after the preposition, such as it, him, them or her. Do not duplicate the relativised object in this standard English relative-clause pattern, even if a corresponding structure in another language would repeat it.

The noun before the clause already supplies that object role. Repeating the same role with a personal pronoun makes this pattern ungrammatical, even when the intended meaning is clear.

Remove a pronoun only when it duplicates the same role. An object with a different role remains: the number I called you from needs you as the person called.

A practical B1 guideline is to leave the preposition at the end in conversation and everyday correspondence. Choose the fronted version deliberately for a report, official letter, contract or presentation to a client.

The relevant preposition appears once in the relative clause. A conspicuous error in early formal writing is placing it both before the pronoun and at the end. That produces a faulty mixture of two alternatives.

When a clause describes a place or time, where or when can often be simpler than in which or on which. These are related tools, but here the target is specifically the preposition + relative pronoun pattern.

A defining clause narrows the reference: it resolves which person or thing is meant. It is attached directly to the noun without enclosing commas.

Pronoun choice is broad: who or that for people, which or that for things. British usage readily accepts defining which; some American editorial guidance reserves which for clauses with commas. The commas work alike in both varieties, so this lesson focuses on punctuation.

When a person or thing is already identified and a separate detail is added, set the relative clause off with commas. A proper name or my/our often helps identify a referent but does not determine punctuation automatically: context still matters.

Removing the clause preserves the core message while losing a detail. This is a useful check before adding commas.

Do not use relative that in a comma-separated supplementary clause. People can take who or object whom; things take which. Whose, where and when can also fit their respective roles.

That is familiar in defining clauses, which can lead to mistakes. For this relative-clause pattern, a comma introducing supplementary information rules out relative that.

A supplementary relative clause inside a sentence needs a comma at each end: one opens it, the other returns to the main clause. Omitting the closing comma is a common punctuation error here.

If the clause ends the sentence, final punctuation replaces the need for a separate closing comma. If it is inside the main clause, close it with a comma. This concerns that clause’s boundaries rather than the total number of commas in the sentence.

The intended meaning in context determines the choice. If my mother, our landlord or a name identifies the person unambiguously, a relative clause can add a comma-separated detail. But our landlord who lives upstairs can distinguish one of several landlords; our does not prohibit a defining clause.

Plural nouns allow both patterns. The students who arrived early selects the early arrivals; The students, who arrived early, adds that detail about the entire already identified group. Do not choose punctuation merely from the noun’s number.

Without commas, a relative clause establishes the group being discussed. With commas, it attributes a property to the already named group. A defining clause alone does not prove that other people necessarily exist outside the group.

Before adding commas, check whether the property actually applies to everyone being discussed. Otherwise, commas can make the claim factually false.

After a comma, which can refer to the entire preceding proposition rather than one noun, commenting on the event as a whole. Relative that cannot do this; the comma is required.

In speech, supplementary clauses normally form a separate intonation group with pauses, while defining clauses are integrated. Different readings of the same wording can convey different information.

This lesson does not practise choosing who/which by noun type, omitting pronouns or placing prepositions within a relative clause. Those are related lessons. Here the axis is punctuation and its consequences.

The repetition occurs in three positions: the verb’s object, the clause’s subject, or the object of a preposition left at the clause’s end.

The error does not depend on the particular relative pronoun: it occurs with that, which and who alike. Correct it by removing the repetition rather than changing the pronoun.

The minimal edit here deletes exactly one word. If the sentence breaks after deletion, the wrong word was removed: the relative pronoun links the clause to the noun and stays in place.

Whose expresses possession or a relationship before a noun phrase: whose ticket, whose new ticket. An adjective can appear between whose and the head noun.

Who’s means who is or who has. Who is can precede a verb form, adjective or noun phrase: who’s waiting, who’s ready, who’s a teacher. Consider the whole clause’s structure and meaning, not just its next word.

The quickest check is to expand the contraction. If who is creates a nonsensical combination in this position, the possessive form is needed.

The possessive form is not limited to people: it can also connect an organisation, building or city with something associated with it.

What itself means “the thing that”: it combines a referent and a relative link. It cannot attach to an already named noun in this standard relative pattern; that would duplicate the referent.

After a noun, English uses an ordinary relative pronoun. In these defining clauses, that and which are natural for things; who and that are natural for people.

First-language interference can make this error persistent: one linking word may serve both purposes elsewhere, but English relative what does not.

Without a preceding head noun, what naturally means “the thing that”: What you said was helpful. It combines a thing and its relative link. This does not mean that every clause without a head noun can only use what.

This “the thing that” pattern can therefore start a sentence with what, without a preceding head noun. Adding a head noun calls for an ordinary relative pronoun instead.

The converse check is to replace what with the thing that. If the sentence remains natural, what fits.

Everything, something, anything, nothing and all already include the sense of a thing. Adding relative what would repeat that sense.

That is often used after these generalising words. Which can also occur depending on construction and style; do not turn a preference for that into an absolute ban. Here we practise that as the basic standard option.

The relative pronoun can sometimes be omitted when it is object, but what does not replace it after these head words in this standard pattern.

Each of this rule’s three errors needs one action. Remove one word for repetition; replace one word for who’s/whose or what/that confusion.

Rewriting the whole sentence has a practical drawback: you can lose a fact or alter the meaning, making the error disappear along with information.

Identify the error type before editing. Otherwise, it is tempting to “fix” the sentence with an unrelated random change.