Subject-Verb Agreement with "One of": The Most Common Exam Trap
Learn how subject-verb agreement works with one of, including one of my friends, one of the students, one of those people who, common mistakes, and practice.
Few subject-verb agreement errors appear in exams as often as one of.
Incorrect: One of my friend is here.
Correct: One of my friends is here.
And then there is the second trap:
Incorrect: One of the students are absent.
Correct: One of the students is absent.
The confusion is understandable. The sentence contains a plural noun like friends, students, or books, so many learners feel that the verb should also be plural. But grammatically, the main subject is not friends or students. The main subject is one.
That is the whole secret behind this pattern. The noun after of must usually be plural, but the verb agrees with one, so the verb is singular.
This article explains the rule clearly, then moves into the real exam traps: one of + plural noun, one of them, and the tricky pattern one of those people who…
For nearby agreement topics, see Collective Nouns: When “Team Is” and “Team Are” Both Work and Why “News Is” Correct.
The phrase one of means one member from a larger group.
One of my friends = one person from the group of my friends
One of the books = one book from the group of books
One of the reasons = one reason from several reasons
So the structure contains two ideas:
- one — the selected single person or thing
- of + plural noun/pronoun — the larger group from which that one is selected
Rule box: Use one of + plural noun/pronoun + singular verb when the whole phrase is the subject.
Basic pattern:
One of my friends is here.
One of the students has called.
One of these answers is correct.
The noun after of is plural because you cannot choose one from only one item. You choose one from many.
Incorrect: one of my friend
Correct: one of my friends
But the verb is singular because the sentence is about one selected member.
Incorrect: One of my friends are here.
Correct: One of my friends is here.
This is different from ordinary plural-subject agreement:
My friends are here.
One of my friends is here.
The second sentence has a plural noun, but the complete subject means only one person.
| Structure | Correct Example | Why |
|---|---|---|
| one of + plural noun + singular verb | One of the boys is absent. | One boy is selected from many boys. |
| one of + plural pronoun + singular verb | One of them has called. | One person from the group has called. |
| one of + determiner + plural noun | One of these books is missing. | The group noun is plural; the verb follows one. |
| one of + superlative + plural noun | One of the best players is injured. | The selected player is one individual. |
The most common grammar test pattern is:
One of + the/my/these/those + plural noun + singular verb
Examples:
One of the teachers is on leave.
One of my cousins has moved to Pune.
One of these ideas seems practical.
One of those mistakes was serious.
Sometimes one of is not the main subject of the whole sentence. It may appear after a linking verb:
He is one of my closest friends.
This was one of the reasons for the delay.
Grammar is one of the areas students ignore.
Here the verb before one of agrees with the real subject before it: he, this, grammar. The phrase one of comes in the complement position.
Compare:
One of the reasons is clear.
This is one of the reasons.
In the first sentence, one of the reasons is the subject. In the second, this is the subject.
With pronouns, the same logic applies:
One of them is responsible.
One of us has made a mistake.
One of you needs to explain this.
Even if them, us, or you refers to several people, the phrase selects one person from the group.
Now comes the trap that separates basic learners from careful writers:
He is one of those people who work hard.
Why work, not works?
Because the relative pronoun who refers to people, not to one. The meaning is:
He is one member of the group of people who work hard.
So in this pattern, the verb inside the relative clause is plural:
Correct: She is one of those students who ask good questions.
Correct: This is one of the books that explain the topic well.
Correct: He is one of the players who train every morning.
But if the sentence says the only one of, the meaning changes:
He is the only one of those people who works on Sundays.
Here only one is being singled out, so who works can refer to that one person.
This is an advanced but very common exam trap.
Use this method whenever you see one of in error spotting, fill-in-the-blanks, or sentence correction.
- Find the full one of phrase.
- Check the noun after of. It should usually be plural.
- Ask whether the one of phrase is the subject of the main verb.
- If yes, use a singular main verb: is, was, has, does, seems, needs.
- If there is a relative clause after the plural noun, check what who/that/which refers to.
- Read the sentence again for meaning.
One of my friend/friends is here.
The phrase means one person from a group. The group noun must be plural. Correct:
One of my friends is here.
One of the students is/are absent.
The full subject is one of the students. The head idea is one. Correct:
One of the students is absent.
He is one of those people who work/works hard.
The relative pronoun who refers to people, a plural noun. Correct:
He is one of those people who work hard.
-
One of my friends is here.
The group noun is friends, but the selected person is one. -
One of the students is absent.
The main verb agrees with one, not students. -
One of them has called.
Them is plural in meaning, but one of them is singular. -
One of these answers is correct.
Only one answer from the group is correct. -
One of the windows was broken.
The sentence is about one window. -
One of my cousins lives in Delhi.
Use lives, not live, because the subject is singular. -
He is one of those people who work hard.
Who refers to people, so the clause uses plural agreement. -
She is one of the students who have completed the project.
The students have completed the project; she is one of them. -
This is one of the reasons that make the rule difficult.
That refers to reasons, so make is plural. -
He is the only one of the players who has scored in every match.
The only one shifts the focus to one individual.
Incorrect: One of my friend is here.
Correct: One of my friends is here.
After one of, the group noun should normally be plural:
one of the boys
one of the questions
one of my relatives
one of these problems
You are choosing one from a group, so the group must contain more than one member.
Incorrect: One of the students are absent.
Correct: One of the students is absent.
The nearest noun students can distract the reader. Do not choose the verb by the nearest noun. Find the head of the subject. In one of the students, the head is one.
This same idea appears in other agreement questions where a nearby plural noun distracts from the real subject. See Why “News Is” Correct for another common example.
Incorrect: One of them have called.
Correct: One of them has called.
Many learners see them and choose have. But the complete subject is one of them, so use has.
More examples:
One of us is wrong.
One of you has the key.
One of them does not understand the rule.
Incorrect: He is one of those people who works hard.
Correct: He is one of those people who work hard.
In this sentence, who refers to people. The relative clause describes the whole group of people. He belongs to that group.
But compare:
He is the only one of those people who works hard.
With the only one, the relative clause can refer to the single person. That is why works becomes possible.
Correct: This is one of the best books I have read.
Correct: She is one of the most intelligent students who have joined this year.
The group noun after a superlative is still plural: books, students, players, ideas.
Do not write:
Incorrect: one of the best book
Correct: one of the best books
In informal speech, people sometimes make agreement mistakes because the plural noun is closer to the verb:
One of my friends are coming.
You may hear this, but in standard written English and exams, it is incorrect. Use:
One of my friends is coming.
The rule is stable in both British and American English.
| Mistake | Correct Form | Reason |
|---|---|---|
| One of my friend is here. | One of my friends is here. | The noun after of should be plural. |
| One of the students are absent. | One of the students is absent. | The main subject is one. |
| He is one of those people who works hard. | He is one of those people who work hard. | Who refers to plural people. |
| One of them have called. | One of them has called. | One of them is singular. |
| One of these answer is right. | One of these answers is right. | The group noun must be plural. |
| One of my cousins live abroad. | One of my cousins lives abroad. | The selected cousin is one person. |
| This is one of the reason for the delay. | This is one of the reasons for the delay. | One reason from several reasons. |
Choose the correct option or correct the error.
- One of my friend/friends is a doctor.
- One of the answers is/are correct.
- One of them has/have taken my notebook.
- She is one of those teachers who explain/explains grammar clearly.
- Error spotting: One of the boys are missing from the class.
- Error spotting: This is one of the best idea in the proposal.
- Error spotting: He is one of those players who trains every day.
- Fill in the blank: One of these phones ___ not working. (is/are)
- Rewrite correctly: One of my cousin live in Jaipur.
- Rewrite correctly: One of the reasons that makes this difficult is pronunciation.
- friends — one from a plural group.
- is — the subject is one of the answers.
- has — one of them is singular.
- explain — who refers to plural teachers.
- One of the boys is missing from the class.
- This is one of the best ideas in the proposal.
- He is one of those players who train every day.
- is — one phone is not working.
- One of my cousins lives in Jaipur.
- One of the reasons that make this difficult is pronunciation.
The one of rule is simple, but the sentence around it can be distracting.
Rule box: Use one of + plural noun/pronoun + singular main verb.
Remember the split:
- The noun after of is plural: one of my friends.
- The main verb is singular: one of my friends is.
- In one of those people who…, the relative clause usually agrees with the plural noun: people who work.
Final examples to revise:
One of my friends is here.
One of the students has answered correctly.
He is one of those people who work quietly but seriously.