That identifies who or what we mean
A defining relative clause supplies information needed for identification. It follows the noun and answers the practical question: which particular person or thing?
That introduces this identifying clause and can refer to a person or thing. In this usage, do not put a comma before the defining clause: the information and noun form one whole.
name of a person or thing + that + identifying description
The nurse that works at reception can help you.
The nurse that works at reception can help you.
That identifies which particular nurse is meant.
Use the laptop that has the blue sticker.
Use the laptop that has the blue sticker.
That has the blue sticker distinguishes the required laptop from others.
One that for people and things
In defining relative clauses, that can replace who for people and which for things or animals. The driver that waited and The bus that stopped therefore have the same structure.
Who for a person and which for a thing often remain entirely grammatical alternatives. This rule aims to teach appropriate that usage, rather than label other standard options incorrect.
That is particularly common in everyday and informal language. In a more formal text, an author may choose who or which, but this is a style choice in a defining clause, rather than a universal ban on that.
person + that or who; thing + that or which
She is the teacher that helped me.
She is the teacher that helped me.
That refers to a person; who is also possible here.
The film that we saw was excellent.
The film that we saw was excellent.
That refers to a thing; which is also possible here.
That as the relative clause’s subject
If the person or thing itself performs the action in the relative clause, that is its subject. The verb follows that directly: the colleague that speaks Spanish, the bus that stops here.
You cannot simply remove this that because the clause would have no subject. Do not add a second subject he, she or it either: that already performs that role.
noun + that + verb
- verb / V —
- A word for an action or state, such as work or be. The pattern determines its form.
- noun —
- A word naming a person, thing or idea: student, book, happiness.
The courier that brought the parcel was friendly.
The courier that brought the parcel was friendly.
That is the subject of brought, so do not omit it.
The app that tracks my hours is free.
The app that tracks my hours is free.
That itself performs tracks; an additional it would be unnecessary.
That as an object: omission is possible
If that is followed by a separate subject, that is the object: the book that you lent me. You performs lent, while book is what was lent.
In a defining relative clause, object that can be kept or omitted: the book that you lent me and the book you lent me. Both are grammatical. If that is kept, do not repeat the object with it, him or her.
noun + (that) + another subject + verb; object that can be omitted
- subject / S —
- The grammatical subject: who or what the clause is about; the verb agrees with it. In The book was written, the book is the subject, although someone else does the action.
- verb / V —
- A word for an action or state, such as work or be. The pattern determines its form.
- object / O —
- Who or what an action affects: in I read a book, a book is the object.
- noun —
- A word naming a person, thing or idea: student, book, happiness.
I found the note that you left.
I found the note that you left.
You is the subject of left, and that is its object. I found the note you left is possible here.
The colleague that we met works upstairs.
The colleague that we met works upstairs.
We performs met, so object that can be omitted without adding him or her.
The boundary: non-defining clauses with commas
A non-defining relative clause adds incidental information about a person or thing already identified. Writing sets off this clause with commas; standard English does not use that here.
Compare The designer that works downstairs can help, which identifies the designer, with Maya, who works downstairs, can help. Maya’s name already identifies the person, and the relative clause only adds information. The second sentence needs who, rather than that.
Identifying description: no commas, that is possible. Additional detail: between commas, who or which.
The café that opens early is near the station.
The café that opens early is near the station.
The description helps select the café, so that without a comma is appropriate.
Our café, which opens at seven, is near the station.
Our café, which opens at seven, is near the station.
Our café is already identified; the information between commas is additional, so which is used.
Position of the noun and pronoun
A defining relative clause usually immediately follows the noun it identifies. This makes it easy to connect the form with that I completed, or the assistant with that speaks Polish.
Relative that replaces the subject or object within the clause. Do not duplicate that same element: not that she works or that I completed it. The minimal correction is to remove the unnecessary pronoun.
The form that I completed is attached.
The form that I completed is attached.
That immediately follows form; repeated it after completed is unnecessary.
Ask the assistant that speaks Polish.
Ask the assistant that speaks Polish.
That follows assistant and is itself the subject of speaks.
Using the rule in speech
First name the person or thing, then add a characteristic that helps the listener choose the intended one: the room that has a projector, the file that you sent, the volunteer that speaks Spanish.
After building the sentence, quickly check who performs the action in the relative clause. If it is that, do not omit it. If a separate subject follows that, that is an object and can be absent. Also check that this really identifies something without commas, rather than adding extra information.
Please send me the file that you prepared this morning.
Please send me the file that you prepared this morning.
The phrase identifies the required file; you is the subject, so that is the object.
Use the room that has a projector.
Use the room that has a projector.
That is the subject of has and helps select the room.
Common mistakes
Incorrect:The woman that she works here is my aunt.
Correct:The woman that works here is my aunt.
That is already the subject of works, so she creates a duplicate subject.
Incorrect:The film that we watched it was excellent.
Correct:The film that we watched was excellent.
That already replaces the object of watched, so it is unnecessary.
Incorrect:My brother, that lives in Lviv, is a chef.
Correct:My brother, who lives in Lviv, is a chef.
The clause between commas adds information about an already-identified person; that is not used in this non-defining clause.
Incorrect:The book that I buyed yesterday was useful.
Correct:The book that I bought yesterday was useful.
Buy has the irregular past form bought. That introduces the description of the book; I is this clause’s subject.
Incorrect:The shop that near my office closes at six.
Correct:The shop that is near my office closes at six.
In the full descriptive clause, that is the subject. The location near my office needs is: that is near my office.