When drafting an essay, editing a workplace report, or writing a breaking news dispatch, subject-verb agreement can occasionally cause hesitation. One of the most frequently searched grammar questions worldwide is whether to write a number of is or are.

The quick answer is: “A number of” always takes a plural verb—so you should use “are,” not “is.”

• Correct: A number of citizens are voting today.
• Incorrect: A number of citizens is voting today.

However, the confusion deepens because changing just one letter—from “a” to “the”—completely flips the rule. While “a number of” takes a plural verb (are), “the number of” requires a singular verb (is).

In this comprehensive guide, we will break down the grammatical mechanics behind this rule, review side-by-side comparisons, provide over 80 real-world examples, and test your skills with a self-assessment quiz.

The Rule Explained: “A Number Of” vs. “The Number Of”

To master this rule, you must understand what the sentence is actually focusing on: the group of items, or the statistical tally itself.

+------------------+---------------+----------------+--------------------------------------+
| Phrase           | Verb Type     | Present Tense  | Meaning                              |
+------------------+---------------+----------------+--------------------------------------+
| A number of...   | Plural Verb   | ARE / WERE     | Means "several," "many," or "some"   |
| The number of... | Singular Verb | IS / WAS       | Refers to a specific total or figure |
+------------------+---------------+----------------+--------------------------------------+

1. Why “A Number Of” Takes “Are”

Grammatically, “a number of” functions as a complex determiner or quantifier, similar to words like many, several, or a few.

Even though the word “number” is grammatically singular in form, idiomatic English treats “a number of [plural noun]” as a plural concept because your focus is on the multiple people, items, or events being discussed.

• Idiomatic meaning: A number of roads are closed. $\rightarrow$ Many roads are closed.

2. Why “The Number Of” Takes “Is”

When you write “the number of,” the word number is the true grammatical subject of the sentence. You are not talking about the individual items; you are talking about the single quantitative metric, total, or integer.

• Idiomatic meaning: The number of applicants is growing. $\rightarrow$ The total figure is growing.

Easy Memory Tricks

Never mix these two phrases up again using these two simple mnemonics:

1. The “A” Rule: A stands for “A lot” or “All.” Both point to plural collections. Therefore, A number of = Are.
2. The “T” Rule: T stands for “The Total.” A total is a single number. Therefore, The number of = The singular verb (Is).

Common Mistakes to Avoid

Mistake 1: Getting distracted by prepositional phrases

Writers often think the prepositional phrase (of employees, of questions) can be ignored to find the subject. While this is true for phrases like “one of the students is,” it does not apply to quantifiers like “a number of.”

• Wrong: A number of doctors thinks the protocol should change.
• Right: A number of doctors think the protocol should change.

Mistake 2: Treating “The number” as plural because of the noun that follows

The plural noun directly behind “the number of” often tricks the ear. Always look at the article (the vs. a).

• Wrong: The number of cybersecurity breaches have increased.
• Right: The number of cybersecurity breaches has increased.

80+ Practical Examples Across Contexts

To help you gain full confidence in this rule across professional, academic, and personal settings, explore these categorized examples.

Basic Everyday Examples

1. A number of guests are waiting outside the hall.
2. A number of packages have arrived this afternoon.
3. A number of apples in the basket are bruised.
4. A number of buses run along this route every hour.
5. A number of children were playing in the courtyard.
6. A number of pens are missing from the desk.
7. A number of dogs are barking down the street.
8. A number of windows were left open during the rain.
9. A number of questions remain unanswered.
10. A number of lights are flickering in the hallway.

Intermediate Examples

11. A number of flight routes were canceled due to severe weather.
12. A number of local businesses have adopted green energy practices.
13. A number of community members support the proposed tax reform.
14. A number of tourists visit the historic landmark every spring.
15. A number of cars are parked illegally near the venue entrance.
16. A number of updates are required before the app can launch.
17. A number of ingredients need to be measured before baking.
18. A number of structural flaws were identified by the inspector.
19. A number of team members prefer working remotely on Fridays.
20. A number of historic buildings face demolition this year.

Advanced & Editorial Examples

21. A number of geopolitical factors influence fluctuating crude oil prices.
22. A number of legislative amendments are currently under review by the committee.
23. A number of economic indicators suggest that interest rates may stabilize soon.
24. A number of international treaties govern maritime navigation rights.
25. A number of epidemiological models predict an early flu season.
26. A number of prominent historians dispute the authenticity of the manuscript.
27. A number of ethical dilemmas arise when implementing automated decision-making.
28. A number of constitutional provisions safeguard freedom of expression.
29. A number of aerospace contractors compete for public defense tenders.
30. A number of fiscal measures have prevented further currency devaluation.

Daily Conversation Examples

31. “A number of us are heading out for lunch if you’d like to come.”
32. “A number of neighbors have complained about the construction noise.”
33. “A number of my friends watch that documentary series.”
34. “A number of stray cats gather near the community garden.”
35. “A number of recipes call for buttermilk instead of whole milk.”
36. “A number of trains are running late this morning.”
37. “A number of shops on the high street close early on Sundays.”
38. “A number of our relatives live across the country.”
39. “A number of library books are past their due dates.”
40. “A number of shoes were left piled by the front door.”

Academic Writing Examples

41. A number of researchers argue that the control group was contaminated.
42. A number of peer-reviewed studies demonstrate the efficacy of the vaccine.
43. A number of participants dropped out prior to the second trial stage.
44. A number of sociological variables correlate with student performance.
45. A number of variables were controlled during the laboratory testing.
46. A number of hypotheses have been formulated to explain the anomaly.
47. A number of archaeological artifacts were uncovered at the excavation site.
48. A number of critical essays examine modernism in post-war literature.
49. A number of algorithms exhibit algorithmic bias in natural language models.
50. A number of data points diverge significantly from the regression line.

Business & Professional Writing Examples

51. A number of stakeholders are expressing concern over the Q3 valuation.
52. A number of our corporate clients require tailored enterprise solutions.
53. A number of board members have voted in favor of the acquisition.
54. A number of regional branches exceeded their performance targets.
55. A number of compliance audits are scheduled for the next quarter.
56. A number of supply chain bottlenecks threaten holiday delivery deadlines.
57. A number of marketing campaigns are currently undergoing A/B testing.
58. A number of external consultants were hired to assist the transition.
59. A number of investment funds have reallocated their capital toward clean tech.
60. A number of human resource policies require immediate updating.

Professional Email Examples

61. “A number of inquiries have come in regarding our software update.”
62. “Please note that a number of files are missing from the shared folder.”
63. “A number of attendees have RSVP’d for tomorrow’s strategy session.”
64. “A number of action items remain pending from our Monday meeting.”
65. “A number of team members are out of the office on personal leave.”
66. “A number of revisions were requested by the client on the latest draft.”
67. “A number of issues were resolved during today’s IT maintenance window.”
68. “We noticed that a number of invoices are still awaiting your signature.”
69. “A number of candidates have completed their initial screening interviews.”
70. “A number of suggestions from your presentation are being implemented.”

ESL / Student Learning Examples

71. A number of students study in the library every afternoon.
72. A number of new words are introduced in this vocabulary chapter.
73. A number of pencils belong in the classroom container.
74. A number of notebooks were distributed before the lesson began.
75. A number of learners find English prepositions challenging.
76. A number of teachers participate in the weekend mentoring workshop.
77. A number of foreign exchange students arrive on campus tomorrow.
78. A number of grammar rules have exceptions you must memorize.
79. A number of practice tests are available on the student portal.
80. A number of chairs are set up in the auditorium for assembly.

Direct Comparison: “A Number Of” vs. “The Number Of”

Notice how changing the article changes the verb choice:

Side-by-Side: Incorrect vs. Correct

+--------------------------------------------------+--------------------------------------------------+
| Incorrect Usage                                  | Correct Usage                                    |
+--------------------------------------------------+--------------------------------------------------+
| A number of delegates is arriving tomorrow.      | A number of delegates are arriving tomorrow.     |
| A number of software bugs was detected.          | A number of software bugs were detected.         |
| The number of active cases have decreased.       | The number of active cases has decreased.        |
| A number of my colleagues disagrees.             | A number of my colleagues disagree.              |
| The number of available seats are limited.       | The number of available seats is limited.        |
| There is a number of options to consider.        | There are a number of options to consider.       |
| A number of changes has taken place.             | A number of changes have taken place.            |
+--------------------------------------------------+--------------------------------------------------+

Study Reference Sheet

Cheat Sheet: Quantifier vs. Metric

• Formula A:A number of + [Plural Noun] + Plural Verb (ARE / WERE / HAVE)
  • Mental test: Replace with “Many”. If “many” fits, use a plural verb.
• Formula B:The number of + [Plural Noun] + Singular Verb (IS / WAS / HAS)
  • Mental test: Replace with “The total”. If “the total” fits, use a singular verb.

Practice Exercises

Fill in the blanks with the correct verb (is / are or has / have):

1. A number of policy changes ________ (is / are) scheduled to take effect in January.
2. The number of road accidents ________ (has / have) dropped significantly since the new speed limit was introduced.
3. There ________ (is / are) a number of reasons why our quarterly revenue increased.
4. The number of subscribers to the journal ________ (remains / remain) high.
5. A number of reporters ________ (was / were) waiting outside the courthouse.

Answer Key with Explanations

1. are — “A number of” acts as a plural quantifier meaning “several policy changes.”
2. has — The focus is on “The number” (a singular statistical total).
3. are — The true semantic subject following the dummy pronoun “there” is plural (“a number of reasons”).
4. remains — “The number” is the singular subject, requiring the singular verb form remains.
5. were — “A number of reporters” refers to multiple journalists, requiring the plural past tense verb were.

5-Question Knowledge Quiz

Test your understanding with these editorial scenarios:

Q1: Which sentence is grammatically correct?
A) A number of participants has submitted their feedback.
B) A number of participants have submitted their feedback.
C) The number of participants have submitted their feedback.
D) The number of participants are sixty.

Q2: Complete the sentence: “The number of days left before the launch _____ shrinking.”
A) are
B) were
C) is
D) have been

Q3: Why does “a number of” take a plural verb?
A) It is an irregular Latin preposition.
B) It functions as a collective quantifier meaning “several” or “many.”
C) It refers to a single figure.
D) It is an exception reserved only for spoken English.

Q4: Select the sentence that uses incorrect subject-verb agreement:
A) A number of analysts expect a market correction.
B) The number of applications was unprecedented.
C) A number of suggestions was brought up during the meeting.
D) The number of applicants is higher than expected.

Q5: Choose the correct verb pair: “A number of birds _____ migrating, but the number of sightings _____ low.”
A) is / is
B) are / are
C) are / is
D) is / are

Quiz Answers

• Q1: B — “A number of” requires the plural auxiliary verb have.
• Q2: C — “The number” refers to a single metric; therefore, use the singular verb is.
• Q3: B — Idiomatically, “a number of” works like “many” or “several.”
• Q4: C — Should be “were brought up”, because “a number of suggestions” requires a plural verb.
• Q5: C — The first clause requires the plural verb (are migrating), while the second requires the singular verb (is low).

Frequently Asked Questions (FAQs)

1. Is “a number of” ever singular in modern English?

No. In modern standard English (including US, UK, Canadian, and Australian conventions), “a number of” followed by a plural noun consistently takes a plural verb. Treating it as singular is considered non-standard and grammatically incorrect.

2. Can you say “a large number of is”?

No. Adding adjectives such as large, small, significant, or growing does not change the core rule. You should write: “A large number of volunteers are needed,” not “is needed.”

3. What verb goes with “a variety of”?

Like “a number of,” the phrase “a variety of [plural noun]” acts as a quantifier and takes a plural verb: “A variety of options are available.” However, “the variety” takes a singular verb: “The variety of plants is impressive.”

4. What happens when “the number of” is followed by a plural noun?

Even though the noun directly preceding the verb is plural (e.g., the number of students), the verb remains singular (is / was / has). The noun in the prepositional phrase does not change the singular nature of the subject noun, number.

5. Does the rule change in past tense?

The core distinction remains identical in the past tense. Use were and had (plural forms) with “a number of,” and use was and had (singular forms) with “the number of.” Example: “A number of issues were noted,” versus “The number of issues was small.”

Conclusion

The debate between “a number of is or are” comes down to one clear guideline:

• Choose ARE (or another plural verb) whenever you use a number of.
• Choose IS (or another singular verb) whenever you use the number of.

Keep the “A = All / Many” and “The = Total” rule in mind whenever you write or edit, and your subject-verb agreement will remain precise, professional, and clear.

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Editorial Disclaimer

*This article is designed for educational, general editorial, and reference purposes. It follows standard descriptive and prescriptive conventions accepted across US, UK, Canadian.

Also Read: Comma Before Which vs That: Rules, Differences, and Examples

More Than One: Is or Are? Grammar Rules & Examples

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