Subject-verb agreement
Subject–verb agreement follows the grammatical head of the subject phrase, not the nearest noun.
01 · Concept foundation
Understand the terms before applying the rule
Each term below names a different grammatical object. Open examples and compare their function rather than memorising a Vietnamese translation alone.
agreement/əˈɡriːmənt/
hòa hợpA grammatical dependency in which the form of one element reflects features such as number or person of another.
The result is; the results are
Kết quả là; các kết quả là
grammatical head/ɡrəˈmætɪkəl hed/
trung tâm ngữ phápThe central word that determines the grammatical properties of a phrase.
The number of stations is increasing. Head: number
Số lượng trạm đang tăng. Trung tâm: number
collective noun/kəˈlektɪv naʊn/
danh từ tập hợpA noun referring to a group, which may take singular or plural agreement depending on variety and intended meaning.
The team is ready. / The team are divided.
Nhóm đã sẵn sàng. / Các thành viên trong nhóm bất đồng.
Complete lesson scope
Do not stop at one formula
Agreement with simple, coordinated and collective subjects
Head nouns inside long noun phrases
Indefinite pronouns, quantities, fractions and percentages
There-constructions and notional versus grammatical agreement
Decision boundary: Ignore nearby nouns that are not the grammatical head when choosing the finite verb.
02 · Controlling rule
Subject–verb agreement normally follows the grammatical head of the subject phrase, not the nearest noun. Coordinated subjects, quantities, indefinite pronouns, collective nouns and existential there require separate decision rules and a consistent variety/register convention.
subject head [person/number] ↔ finite verbSubject–verb agreement
Find the grammatical head of simple and complex subjects, then select a finite verb form that matches number and person without being distracted by nearby nouns.
Agreement follows the head
The verb agrees with the head of the subject phrase, not with the noun nearest to the verb.
subject head [number/person] ↔ finite verbIgnore nouns inside of-phrases, prepositional phrases and relative clauses when locating the head.
Third-person singular present forms normally take -s; other present forms use the base form except be.
A subject complement never controls agreement with the verb.
The accuracy of the forecasts is improving.
- Head: accuracy
- Verb: is improving
The forecasts from the offshore station are improving.
High-risk subject patterns
Underline the head before selecting the finite verb.
| Subject pattern | Agreement | Example |
|---|---|---|
| the number of + plural noun | singular | The number of stations is increasing. |
| a number of + plural noun | plural | A number of stations are offline. |
| each/every + singular noun | singular | Each sensor has an identifier. |
| X and Y | usually plural | Wind and waves affect transport. |
| either X or Y | usually nearest subject | Either the gauges or the logger is faulty. |
Agreement decision sequence
Use grammatical analysis first and notional interpretation second.
| Step | Question | Action |
|---|---|---|
| 1 | What is the full subject phrase? | Bracket it before the verb. |
| 2 | What is the grammatical head? | Ignore modifiers and embedded nouns. |
| 3 | Is the head singular, plural or coordinated? | Apply the relevant rule. |
| 4 | Does register/variety allow notional agreement? | Choose one convention consistently. |
High-risk contrasts
Number is the singular head of the subject phrase.
A number of means several and takes plural agreement.
Each is grammatically singular even when followed by a plural of-phrase.
The plural post-verbal noun phrase motivates are in formal writing.
Concept and form check
Apply the system in context
Audit one IELTS-style paragraph for agreement. Underline every subject head and circle every finite verb before correcting the paragraph.
- ✓Locate the full subject phrase and its head.
- ✓Check coordinated, quantified and existential subjects separately.
- ✓Apply one British or American convention consistently for collective nouns and data.
03 · Worked examples
Observe form, function and meaning together
The accuracy of the forecasts is improving.
Độ chính xác của các dự báo đang được cải thiện.
A number of stations are offline.
Một số trạm đang ngoại tuyến.
The number of stations is increasing.
Số lượng trạm đang tăng.
Neither the sensors nor the controller is responding.
Cả cảm biến lẫn bộ điều khiển đều không phản hồi.
There are several unresolved discrepancies.
Có một số sai khác chưa được giải quyết.
04 · High-risk contrast
Explain why one form fails, not only which answer is correct
Each of the stations have a backup sensor.
Each of the stations has a backup sensor.
Each is the singular grammatical head; the plural noun inside the of-phrase does not control agreement.
05 · Mastery check
Apply the rule before marking the lesson complete
Which sentence is grammatically acceptable in the target system?
Which description best defines “agreement”?
Which example is one of the verified target patterns in this lesson?
Which structural formula belongs to this lesson?
Complete all four checks, then submit a sentence for target-form feedback.
06 · IELTS Academic
Transfer grammar into a real communicative task
Agreement control is especially important in Task 1 sentences containing percentages, long noun phrases and there-constructions.
Find the head inside a long noun phrase.
Distinguish a number of from the number of.
Apply agreement with each/every and either/or structures.
Control agreement in existential there and collective-noun sentences.