Who, Which or That? Describe Exactly What You Mean

You need the colleague responsible for a project, not just any colleague. “The colleague who manages the project” helps the listener identify the right person. Relative clauses let you attach identifying or extra information to a noun without starting a separate sentence every time.

Before studying the explanation, try to answer the practice task below without looking at its answer key. Keep your first attempt. It gives you something concrete to compare with a later answer and helps you identify which part of this topic needs attention.

Attach identifying information to a noun

A defining relative clause identifies which person or thing you mean: “The student who asked the question is waiting.” Who commonly refers to people; which refers to things; that can refer to people or things in many defining clauses. Ordinary defining clauses do not use separating commas.

The information may be essential for identification. If there are several students, “the student” alone may be unclear. Add the detail that distinguishes the right one. You do not need the longest description; a short, relevant action often identifies a person more effectively than a list of adjectives.

Avoid adding an unnecessary second subject

“The person who lives next door” already has who as the relative-clause subject. Avoid “the person who he lives next door”. The same issue appears with things: “the app that helps me practise”, rather than “the app that it helps me practise”.

Join two sentences to see the structure: “I know a tutor. The tutor teaches pronunciation.” A natural combined version is “I know a tutor who teaches pronunciation.” Replace the repeated noun with who and keep the verb. Reading the combined version aloud can reveal an extra subject more clearly than staring at punctuation.

Omit the pronoun only in suitable cases

In “the book that I bought”, I is the subject of bought and that represents the object. In a defining clause, you can often say “the book I bought”. In “the book that changed my mind”, that is the subject and cannot simply disappear.

Try asking who performs the action inside the clause. If I bought it, an existing subject remains when that is removed. If the book changed something, removing that leaves the relative clause without a subject. This practical check is more useful than memorising that relative pronouns are always optional.

Separate extra information with commas

A non-defining clause adds extra information about an already identified referent: “Maya, who lives next door, teaches English.” Use commas to mark the extra information. In standard non-defining clauses, use who or which rather than that, and keep the relative pronoun.

The comma can change meaning. “My brothers who live nearby visit often” identifies the nearby brothers among a possible larger group. “My brothers, who live nearby, visit often” presents living nearby as extra information about the brothers being discussed. Decide what you mean before treating commas as decoration.

Try it before reading the answer

Combine “I need the file. You sent the file yesterday.” Decide whether that can be omitted in “The teacher that helped me was kind.” Repair “The woman who she called is my manager” when the intended meaning is a woman performing the call. Add extra information about the named person Omar.

Say or write a complete response, rather than naming only a rule. Where the task asks you to explain a choice, connect that explanation to the meaning or situation. If more than one answer could fit, state the interpretation you are using instead of pretending the context settles everything.

Check the answer and the reason

I need the file that you sent yesterday; “the file you sent yesterday” also works. That cannot be omitted from “the teacher that helped me” because it is the subject. For the stated meaning, say “The woman who called is my manager.” Extra information: “Omar, who works upstairs, will join us.”

Compare the model with your first attempt. Choose one useful correction and make a new example with different content. If your original answer was also valid, explain why it fits. The answer key illustrates the requested task; it is not a complete list of every possible English sentence in a different context.

Make this a short practice session

Use the lesson in three passes: understand a checked example, retrieve the language without viewing it, and use it in a new message. Spend more attention on the part that blocked your first attempt. You can practise alone with a recording or with a partner who can ask a relevant follow-up. Keep your notes focused on one observable skill.

Return to the task after a gap and change one detail. Notice whether you can adapt the language while keeping the intended meaning clear. Record specific evidence such as a correct question form, a phrase recalled without help or an uncertainty you still need to check. One exercise can guide the next practice session without establishing a whole language level.

Continue with a related Sunny Academy activity

Choose a practice activity that matches the obstacle you noticed in this lesson. Use the same idea in a different task so you can see whether you can apply it beyond the examples here.

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