1. My uncle, ____ lives in York, is visiting.
Answer & explanation
who
My uncle, who lives in York, is visiting.
Non-defining clauses add extra information, use commas, retain the relative pronoun and do not use that.
THE IDEA, SIMPLY
The rule, with an example
Separate extra information with commas. Use who for people and which for things. Do not use that or omit the relative pronoun in a non-defining clause.
SEE IT IN CONTEXTOur library, which opened last year, has a quiet study room.
Skills to work on in this practice
- Add extra information with commas
- Choose who or which rather than that
- Keep the relative pronoun in place
Mark extra information with commas
| Use | Example | Why it works |
|---|---|---|
| Extra fact | My tutor, who lives nearby, cycles to work. | The tutor is already identified. |
| Thing | This laptop, which I bought last year, is reliable. | The clause adds a comment about this laptop. |
| Possession | Maya, whose notes I borrowed, helped me revise. | Whose can introduce extra information about possession. |
Common mistake
Check: My tutor, that lives nearby, cycles
Use: My tutor, who lives nearby, cycles
Do not use that in a non-defining relative clause.
How should I practise this?
Read the example and explain the choice before answering. After the exercise, write a new sentence using the same pattern. Revisit any answer you could not explain, even if you guessed correctly.
MORE PRACTICE · SAME TOPIC
Your four practice sets
4 sets · 40 exercises · about 50–70 minutes with writing and review.
10 scored questions, 20 sentence exercises and 10 writing challenges. Time depends on your pace. Start with the quiz or choose the practice you need.
Your scored quiz and self-reviewed exercises are tracked separately on this device.
Questions 1–5 build confidence; 6–10 check transfer and detail. Use Practice for feedback after each answer, or Test yourself to check at the end.
Practise, then understand your answers
10 questions · 10 XP per correct answer · explanations included
Answer every question to see your score.0 / 10 answered
Question 1
My brother, ___ lives in Leeds, is visiting.
- that
- who
- what
Answer & explanation
who. Who introduces extra information about a person.
Question 2
The museum, ___ we visited on Sunday, was fascinating.
- which
- that
- no pronoun
Answer & explanation
which. Which is required; it cannot be omitted in this non-defining clause.
Question 3
Choose the correct punctuation.
- Leila who is my tutor helped me.
- Leila, who is my tutor, helped me.
- Leila, who is my tutor helped me.
Answer & explanation
Leila, who is my tutor, helped me.. The extra-information clause is enclosed in two commas.
Question 4
Can we use that after the comma here?
- Yes
- No
- Only for people
Answer & explanation
No. That is not used to introduce a non-defining relative clause.
Question 5
Our teacher, ___ office is upstairs, is available today.
- whose
- who
- which
Answer & explanation
whose. Whose expresses possession in defining and non-defining clauses.
Question 6
My sister, ___ lives in Leeds, is visiting.
- where
- who
- that
Answer & explanation
who. Who introduces extra information about a person. That is not used in a non-defining clause.
Question 7
Choose the correctly punctuated sentence.
- Paris, which is in France, attracts visitors.
- Paris which is in France, attracts visitors.
- Paris, that is in France, attracts visitors.
Answer & explanation
Paris, which is in France, attracts visitors.. The extra information is enclosed by two commas; which refers to the city.
Question 8
Our car, ___ we bought last year, needs repairs.
- that
- who
- which
Answer & explanation
which. Which introduces a non-defining clause about a thing; it cannot be replaced by that here.
Question 9
Can you omit which in “My laptop, which I bought last month, is broken”?
- Only if you keep the commas.
- No, retain it in this non-defining clause.
- Yes, always omit object pronouns.
Answer & explanation
No, retain it in this non-defining clause.. Unlike defining clauses, non-defining clauses retain the relative pronoun even when it is an object.
Question 10
Sam, ___ father is a chef, loves cooking.
- whose
- who
- which
Answer & explanation
whose. Whose expresses possession within the extra-information clause.
SET 2 OF 4 · 10–15 minutes
Build the pattern
Complete the missing words, then compare the expected form. More than one natural answer may be possible; use the cue and explanation.
2. Our house, ____ was built in 1920, needs repairs.
Answer & explanation
which
Our house, which was built in 1920, needs repairs.
Non-defining clauses add extra information, use commas, retain the relative pronoun and do not use that.
3. Nora, ____ brother is a pilot, loves travel.
Answer & explanation
whose
Nora, whose brother is a pilot, loves travel.
Non-defining clauses add extra information, use commas, retain the relative pronoun and do not use that.
4. This bicycle, ____ I bought last year, is reliable.
Answer & explanation
which
This bicycle, which I bought last year, is reliable.
Non-defining clauses add extra information, use commas, retain the relative pronoun and do not use that.
5. Mr Lee, ____ teaches art, organised the exhibition.
Answer & explanation
who
Mr Lee, who teaches art, organised the exhibition.
Non-defining clauses add extra information, use commas, retain the relative pronoun and do not use that.
6. Edinburgh, ____ is in Scotland, attracts many visitors.
Answer & explanation
which
Edinburgh, which is in Scotland, attracts many visitors.
Non-defining clauses add extra information, use commas, retain the relative pronoun and do not use that.
7. My phone, ____ has a cracked screen, still works.
Answer & explanation
which
My phone, which has a cracked screen, still works.
Non-defining clauses add extra information, use commas, retain the relative pronoun and do not use that.
8. Aisha, ____ essay won the prize, thanked her teacher.
Answer & explanation
whose
Aisha, whose essay won the prize, thanked her teacher.
Non-defining clauses add extra information, use commas, retain the relative pronoun and do not use that.
9. The main hall, ____ seats two hundred people, is full.
Answer & explanation
which
The main hall, which seats two hundred people, is full.
Non-defining clauses add extra information, use commas, retain the relative pronoun and do not use that.
10. My parents, ____ are retired, travel often.
Answer & explanation
who
My parents, who are retired, travel often.
Non-defining clauses add extra information, use commas, retain the relative pronoun and do not use that.
SET 3 OF 4 · 10–15 minutes
Check the details
Complete the missing words, then compare the expected form. More than one natural answer may be possible; use the cue and explanation.
1. Our guide, ____ spoke excellent English, explained the route.
Answer & explanation
who
Our guide, who spoke excellent English, explained the route.
Non-defining clauses add extra information, use commas, retain the relative pronoun and do not use that.
2. The river, ____ flooded last winter, is low today.
Answer & explanation
which
The river, which flooded last winter, is low today.
Non-defining clauses add extra information, use commas, retain the relative pronoun and do not use that.
3. Sam, ____ desk is beside mine, is on holiday.
Answer & explanation
whose
Sam, whose desk is beside mine, is on holiday.
Non-defining clauses add extra information, use commas, retain the relative pronoun and do not use that.
4. My passport, ____ I keep in a drawer, expires soon.
Answer & explanation
which
My passport, which I keep in a drawer, expires soon.
Non-defining clauses add extra information, use commas, retain the relative pronoun and do not use that.
5. The twins, ____ both play tennis, entered the competition.
Answer & explanation
who
The twins, who both play tennis, entered the competition.
Non-defining clauses add extra information, use commas, retain the relative pronoun and do not use that.
6. Our school, ____ opened in 1985, has a new library.
Answer & explanation
which
Our school, which opened in 1985, has a new library.
Non-defining clauses add extra information, use commas, retain the relative pronoun and do not use that.
7. Rita, ____ painting is on the wall, works nearby.
Answer & explanation
whose
Rita, whose painting is on the wall, works nearby.
Non-defining clauses add extra information, use commas, retain the relative pronoun and do not use that.
8. This suitcase, ____ weighs almost nothing, is useful.
Answer & explanation
which
This suitcase, which weighs almost nothing, is useful.
Non-defining clauses add extra information, use commas, retain the relative pronoun and do not use that.
9. My aunt, ____ works in a hospital, finishes late.
Answer & explanation
who
My aunt, who works in a hospital, finishes late.
Non-defining clauses add extra information, use commas, retain the relative pronoun and do not use that.
10. The old theatre, ____ closed last year, will reopen.
Answer & explanation
which
The old theatre, which closed last year, will reopen.
Non-defining clauses add extra information, use commas, retain the relative pronoun and do not use that.
SET 4 OF 4 · 20–30 minutes
Use it yourself
Write an original answer for each task. Review the guidance to check your work. These are self-review tasks, not automatic grammar grading.
1. Add extra information about a named friend.
What to check
Your wording can vary.
Put the who clause between commas.
Check both the form and the meaning. If you are unsure, compare the lesson explanation before marking this exercise reviewed.
2. Add extra information about an already identified object.
What to check
Your wording can vary.
Use which, not that, and include the commas.
Check both the form and the meaning. If you are unsure, compare the lesson explanation before marking this exercise reviewed.
3. Describe the possession of a named person.
What to check
Your wording can vary.
Use whose within a non-defining clause.
Check both the form and the meaning. If you are unsure, compare the lesson explanation before marking this exercise reviewed.
4. Write a clause at the end of a sentence about your own car.
What to check
Your wording can vary.
Use a comma before the additional which clause.
Check both the form and the meaning. If you are unsure, compare the lesson explanation before marking this exercise reviewed.
5. Write a sentence with a non-defining clause in the middle.
What to check
Your wording can vary.
Use a comma on each side of the extra information.
Check both the form and the meaning. If you are unsure, compare the lesson explanation before marking this exercise reviewed.
6. Explain why that is unsuitable in this kind of clause.
What to check
Your wording can vary.
Non-defining relatives use who, which or another suitable relative form, not that.
Check both the form and the meaning. If you are unsure, compare the lesson explanation before marking this exercise reviewed.
7. Show why a non-defining object pronoun must remain.
What to check
Your wording can vary.
Give an example such as My book, which I lent you, is missing.
Check both the form and the meaning. If you are unsure, compare the lesson explanation before marking this exercise reviewed.
8. Add information about two already identified people.
What to check
Your wording can vary.
Use who with a plural verb where appropriate.
Check both the form and the meaning. If you are unsure, compare the lesson explanation before marking this exercise reviewed.
9. Rewrite two statements about a named city as one sentence.
What to check
Your wording can vary.
Use a non-defining which clause for the extra information.
Check both the form and the meaning. If you are unsure, compare the lesson explanation before marking this exercise reviewed.
10. Remove the extra clause from your own sentence and check its core meaning.
What to check
Your wording can vary.
The main clause should still identify its subject and communicate a complete thought.
Check both the form and the meaning. If you are unsure, compare the lesson explanation before marking this exercise reviewed.
Printable practice
Print this lesson’s original questions with a separate answer key. Use the worksheet for another round without looking at the explanations.
BEYOND MULTIPLE CHOICE
Can you use it yourself?
Try these two tasks before opening the answers. They practise explanation and writing; they do not change your quiz score.
1. Explain or repair
Repair: My laptop, that I bought last year, still works.
Check the reasoning
My laptop, which I bought last year, still works. Use which, not that, for this extra-information clause. Keep both commas.
2. Make the meaning
Add an extra fact about your already identified neighbour, who speaks French.
Compare a possible answer
My neighbour, who speaks French, helped me with the phrase. The commas mark an added fact rather than selecting which neighbour.
Other wording may be correct. Compare the meaning and verb pattern, not just the words.
RELATED PRACTICE
Defining vs non-defining clauses
See how commas change what your sentence means.