After a fraction or percentage followed by of, the noun that names the measured amount or counted members normally controls whether the verb is singular or plural. This guide is for a Primary 6 learner who can often complete the easy part of a question but loses accuracy when a familiar word, number relationship, observation or piece of evidence is used too broadly. The difficulty is not usually a lack of effort. It is a control problem: the mind recognises something useful and stops checking before the task contract has been fully satisfied.
The repair is to separate three moves. First, identify exactly what the information establishes. Second, identify what it does not establish. Third, connect only the supported conclusion to the wording of the question. That three-part habit is small enough to use under examination pressure and strong enough to prevent many confident but unsupported answers.
This article develops that habit through mechanism-led explanation, worked examples, misconception repair, independent practice, delayed transfer and examination control. It belongs to the complete Learner’s Guide volume directory and continues the earlier PSLE Learning Guide foundation. The current official subject documents can be reached through SEAB’s 2026 PSLE formats page; always use the document for the year in which you will sit the examination.
The learner problem
A learner sees a percentage and automatically chooses a singular verb because the percentage is written as one number. That shortcut fails in “Sixty per cent of the pupils are ready”. The sentence is about pupils, a plural countable group, so the verb is plural. In “Sixty per cent of the rice is cooked”, the sentence is about rice as an uncountable amount, so the verb is singular.
The word immediately before the verb may also distract. In “One-third of the boxes is damaged”, the singular-looking fraction does not rescue the sentence. The quantified noun boxes is plural, and the standard agreement is “One-third of the boxes are damaged”. The fraction tells how much or how many; the noun tells what is being quantified.
Meaning still matters when the noun phrase can be viewed in more than one way. A percentage of “the team” may refer to members, while “the team” as one organisation can be singular in another construction. For PSLE editing, use the visible noun and intended meaning, then reread the complete sentence rather than following a mechanical nearest-word rule.
Find the quantity phrase, ask what is being counted or measured, and let that noun control the verb.
The mechanism: what is really happening
A phrase such as “half of the cake” has a partitive structure. Half identifies a portion, while cake identifies the substance or whole being portioned. Because cake is singular, “Half of the cake is gone” uses a singular verb. In “Half of the cakes are gone”, the plural noun cakes changes the agreement even though half remains unchanged.
Percentages work in the same way. The symbol does not possess grammatical number by itself in these sentences. “Twenty per cent of the water has evaporated” treats water as an uncountable amount. “Twenty per cent of the bottles have leaked” refers to multiple bottles. The verb follows the grammatical number of the quantified noun phrase.
Pronouns can perform the same job. “Some of it is missing” is singular because it refers to one substance or thing through it. “Some of them are missing” is plural because them refers to multiple members. This contrast is a useful repair test when a long noun phrase makes the agreement difficult to hear.
Do not confuse this pattern with sentences whose true subject is “the percentage” or “the fraction” itself. “The percentage of absent pupils is lower today” has the singular subject percentage; the following of-phrase identifies the percentage. Compare it with “Ten per cent of the pupils are absent”, where the percentage expression quantifies the pupils directly.
A compact decision routine
- Box the complete fraction or percentage phrase.
- Underline the noun or pronoun after of that names what is quantified.
- Classify that target as singular amount, singular thing or plural members.
- Choose the verb form that agrees with the target meaning.
- Reread to check whether percentage or fraction is itself the subject.
Say the routine aloud during practice until it becomes internal: quantity, target noun, number, verb, whole-sentence check. The purpose is not to make every answer slow. It is to make the checking stage reliable enough that speed can grow safely.
Precise worked examples
Worked example 1: uncountable amount
Prompt. Choose is or are: “Three-quarters of the flour ___ used.”
Reasoning. Flour is an uncountable amount and takes singular agreement.
Answer. Three-quarters of the flour is used.
Control check. Replace the phrase with it: “It is used.”
Worked example 2: plural members
Prompt. Choose has or have: “Three-quarters of the runners ___ finished.”
Reasoning. Runners is plural and the fraction quantifies several people.
Answer. Three-quarters of the runners have finished.
Control check. Replace runners with them: “They have finished.”
Worked example 3: one object
Prompt. Complete: “Half of the orange ___ rotten.”
Reasoning. One orange is being divided conceptually into parts.
Answer. Half of the orange is rotten.
Control check. The noun orange is singular.
Worked example 4: several objects
Prompt. Complete: “Half of the oranges ___ rotten.”
Reasoning. The fraction selects members from a plural set.
Answer. Half of the oranges are rotten.
Control check. The unchanged fraction does not control agreement.
Worked example 5: percentage of water
Prompt. Edit: “Forty per cent of the water have leaked away.”
Reasoning. Water is treated as a single uncountable amount.
Answer. Forty per cent of the water has leaked away.
Control check. Use has with the singular mass noun.
Worked example 6: percentage of containers
Prompt. Edit: “Forty per cent of the containers has cracked.”
Reasoning. Containers is plural.
Answer. Forty per cent of the containers have cracked.
Control check. The sentence concerns multiple containers.
Worked example 7: percentage as subject
Prompt. Choose the verb: “The percentage of correct answers ___ rising.”
Reasoning. The head noun percentage is singular; of correct answers only specifies it.
Answer. The percentage of correct answers is rising.
Control check. This differs from “Fifty per cent of the answers are correct”.
Worked example 8: pronoun test
Prompt. Complete both: “Some of it ___ missing; some of them ___ missing.”
Reasoning. It is singular, while them is plural.
Answer. Some of it is missing; some of them are missing.
Control check. The pronoun exposes the intended number.
Common misconceptions and targeted repairs
Misconception 1: every percentage takes a singular verb
Why it happens. The percentage is seen as one numerical value.
Targeted repair. Look through the number to the quantified noun.
Micro-test. Why are pupils plural in “70% of the pupils”?
Misconception 2: the fraction word controls agreement
Why it happens. Half or one-third looks singular.
Targeted repair. Compare “half of the cake” with “half of the cakes”.
Micro-test. Which word changes between the pair?
Misconception 3: the nearest noun always controls
Why it happens. A surface-position shortcut replaces subject analysis.
Targeted repair. Decide whether the of-phrase is quantified or merely identifies a percentage.
Micro-test. What is the head subject in “The percentage of errors is falling”?
Misconception 4: all collective nouns behave identically
Why it happens. Team, class and group are treated as fixed labels.
Targeted repair. Read the intended meaning and follow the expected school variety consistently.
Micro-test. Does the sentence quantify the group or its members?
Misconception 5: is sounds more formal than are
Why it happens. Formality is confused with agreement.
Targeted repair. Choose by grammatical number, not by tone.
Micro-test. Would formal writing make “half of the books is” correct?
Misconception 6: a correct verb proves the sentence is clear
Why it happens. Agreement is checked without checking the referent.
Targeted repair. Name exactly what the percentage measures.
Micro-test. Could “50% is ready” be unclear without a noun?
Graded independent practice
Attempt each item before opening its explanation in your mind. Write the smallest complete answer that proves the required idea. The questions rise from recognition to explanation and transfer; accuracy matters more than rushing.
Practice 1: recognition
Question. Choose is or are: “Two-thirds of the field ___ flooded.”
Explained answer. Is, because field is one singular area.
Practice 2: recognition
Question. Choose is or are: “Two-thirds of the fields ___ flooded.”
Explained answer. Are, because fields is plural.
Practice 3: mass noun
Question. Complete: “Most of the milk ___ fresh.”
Explained answer. Is fresh.
Practice 4: plural noun
Question. Complete: “Most of the cartons ___ sealed.”
Explained answer. Are sealed.
Practice 5: percentage
Question. Edit “Thirty per cent of the sand were removed.”
Explained answer. Thirty per cent of the sand was removed.
Practice 6: percentage
Question. Edit “Thirty per cent of the stones was removed.”
Explained answer. Thirty per cent of the stones were removed.
Practice 7: fraction
Question. Complete: “One-fifth of the route ___ uphill.”
Explained answer. Is uphill; route is singular.
Practice 8: fraction
Question. Complete: “One-fifth of the routes ___ closed.”
Explained answer. Are closed; routes is plural.
Practice 9: pronoun
Question. Complete: “All of it ___ available.”
Explained answer. Is available.
Practice 10: pronoun
Question. Complete: “All of them ___ available.”
Explained answer. Are available.
Practice 11: head noun
Question. Choose the verb: “The number of damaged chairs ___ small.”
Explained answer. Is; number is the singular subject.
Practice 12: quantifier
Question. Choose the verb: “A number of chairs ___ damaged.”
Explained answer. Are; a number of means several.
Practice 13: contrast
Question. Explain the difference between “25% of the class is absent” and “25% of the pupils are absent”.
Explained answer. The first treats class as the quantified singular group in the chosen wording; the second explicitly quantifies plural pupils.
Practice 14: editing
Question. Correct only what is necessary: “Half of the equipment have arrived.”
Explained answer. Half of the equipment has arrived.
Practice 15: editing
Question. Correct only what is necessary: “Half of the devices has arrived.”
Explained answer. Half of the devices have arrived.
Practice 16: construction
Question. Write a sentence with 60% and a singular verb.
Explained answer. Example: “Sixty per cent of the juice is frozen.”
Practice 17: construction
Question. Write a sentence with 60% and a plural verb.
Explained answer. Example: “Sixty per cent of the cups are clean.”
Practice 18: examination control
Question. What two questions should you ask before selecting the verb?
Explained answer. What is being quantified, and is that target singular, uncountable or plural?
Delayed transfer: use the idea after the surface changes
Do not repeat these transfer tasks immediately after the worked examples. Leave at least one study session between learning and transfer. Delay removes the comfort of short-term imitation and reveals whether the mechanism can be reconstructed from memory.
Transfer 1: science report
New setting. A result states that 80% of the water has evaporated.
What transfers. Treat water as an uncountable amount and use singular agreement.
Answer check. Do not let the numerical size of 80 alter the grammar.
Transfer 2: mathematics explanation
New setting. A solution says three-fifths of the counters are red.
What transfers. Counters is plural, so the verb is plural.
Answer check. The fraction describes how many counters belong to the subset.
Transfer 3: comprehension editing
New setting. A long sentence places several nouns between the quantified noun and verb.
What transfers. Box the whole partitive phrase and recover its head meaning.
Answer check. Do not obey the closest visible noun automatically.
Transfer 4: situational writing
New setting. You report attendance as a percentage of pupils.
What transfers. Use a plural noun if you want the verb to make the member meaning explicit.
Answer check. Prefer clarity over an ambiguous collective noun.
Transfer 5: data commentary
New setting. The percentage itself changes across months.
What transfers. Use singular agreement when percentage is the grammatical subject.
Answer check. “The percentage has increased,” not “have increased”.
Transfer 6: delayed retrieval
New setting. A week later, reconstruct the cake/cakes contrast.
What transfers. Use the unchanged fraction with different nouns to retrieve the rule.
Answer check. If the verb changes with the noun, the mechanism is remembered.
Build a proof-quality answer
A correct thought can still produce an incomplete written answer. To make your reasoning visible, build the response from three parts: a claim that answers the exact question, evidence drawn from the given sentence, quantities, observation or condition, and a bridge explaining why that evidence supports the claim. The bridge is often the missing part. Learners commonly copy a relevant fact and expect the examiner to infer the connection. Instead, write the relationship explicitly. In a short-response item, each part may be only a phrase; in an explanation item, it may take a complete sentence.
The claim should be no broader than the evidence. If the information proves only what happens in one stated case, do not turn it into a universal rule. If a comparison identifies which value is greater, do not invent the size of the difference. If a word modifies an adjective in one sentence, do not claim that it must have the same job in every sentence. Precision is not timid writing. It is the discipline of matching the strength of the conclusion to the strength of the support.
The evidence should be selected rather than copied wholesale. Ask, “Which detail changes the answer?” A complete prompt may contain setting, names, decorative numbers and contextual sentences that make the question readable but do not justify the conclusion. Circle the smallest decisive detail. Then test it by removal: if deleting the detail would make your answer unsupported or change it, the detail is probably doing real evidential work. If deleting it changes nothing, it may be background rather than proof.
The bridge names the mechanism. Useful bridge language includes “because this means…”, “therefore the two values must…”, “this modifies… rather than…”, “so the rate changes while the starting amount remains…”, and “this fact is relevant but does not establish…”. Do not copy these stems mechanically. Use the one that expresses the actual relationship. A bridge earns its place when it would help a careful classmate see why the evidence, and not some other fact, leads to the claim.
The boundary sentence
After drafting the answer, add a silent boundary sentence in your mind: “This does not yet prove that…” Complete it with the most tempting overstatement. The boundary sentence exposes hidden leaps. For example, an observation over a fixed time does not necessarily prove what happens until completion; a parity condition does not by itself identify two numbers; a familiar suffix does not settle word class; and a relevant detail does not guarantee that all required information is present. You do not always write the boundary sentence in the final response, but thinking it protects the sentence that you do write.
The opposite-case test
Try to imagine a case in which the given evidence remains true but your proposed conclusion becomes false. If such a case is possible under the question’s conditions, the conclusion is too strong or something is missing. This is a powerful test because it turns vague doubt into a concrete counterexample. Keep the counterexample small. Change one feature only, preserve the stated information and see whether the answer survives. When it fails, repair the conclusion or name the additional information that would be needed.
The language-strength ladder
Notice the strength of common answer words. “May” expresses possibility. “Is likely to” expresses a supported tendency, not certainty. “Will” states a definite outcome. “Always” and “never” claim no exceptions within the stated domain. “More than” gives an order; “twice as much” gives a multiplicative comparison; an exact value gives still more information. Choose the lowest rung that fully answers the question and is fully supported. Moving higher without evidence creates error; staying lower when the evidence is decisive creates an incomplete answer.
A diagnostic laboratory for independent learners
Use the following laboratory with four questions from your own schoolwork. Choose one that you answered correctly with confidence, one that you answered correctly by guessing, one that you answered incorrectly, and one that you left incomplete. This mixture matters. Studying only wrong answers can hide fragile success, while studying only correct answers can hide the point at which the method breaks down. Place the four responses on separate pages or separate sections so that you can annotate them without rewriting history.
Pass 1: reconstruct the first decision
Cover the marking and solution. For each item, write the first meaningful decision you made after reading: the word you classified, the relationship you selected, the variable you treated as fixed, or the detail you believed was sufficient. Do not write “I started solving”. Name the decision precisely. Many later errors are consequences of an early classification. Finding that point is more useful than circling the final wrong word because the early decision is what must change next time.
Pass 2: separate knowledge from control
Ask whether the error came from missing knowledge or from failing to control knowledge you already possessed. A knowledge gap means you could not state or reconstruct the needed concept even without time pressure. A control gap means you knew the concept but selected it too quickly, ignored a condition, overgeneralised it or failed to check the conclusion. The repairs differ. Knowledge needs explanation, examples and retrieval. Control needs contrasting cases, decision routines and deliberate checking. Calling both problems “carelessness” prevents either from being repaired.
Pass 3: mark the evidence chain
Use three simple labels beside the response: C for claim, E for evidence and B for bridge. If a label is missing, add the missing part in a different colour. If the response contains two claims, check each one separately; evidence for the first claim may not support the second. If a sentence contains several facts, underline only the decisive one. This annotation makes completeness visible and teaches you to produce an answer whose logic can be checked line by line.
Pass 4: write a minimal repair rule
Finish each analysis with a repair rule of no more than twelve words. It must describe an action you can perform, not a feeling you hope to have. “Be more careful” is not usable. “Name the modifier’s target before naming its class”, “check same parity before halving”, “separate rate from starting amount”, and “list what is still missing” are usable because they tell the brain what to do. Reuse the rule on a new question within two days, then revise it if it does not trigger the right behaviour.
Create your own contrast set
Deep understanding grows when you can create neighbouring cases that require different answers. Start with one correct example from this guide. Make Version A by changing a surface detail that should not change the reasoning. Make Version B by changing one decisive condition that should change the answer. Make Version C by removing a necessary detail so that the answer can no longer be determined or justified. Write the answer and the reason for all three versions before asking anyone to check them.
A useful Version A tests whether you are distracted by appearance. You might change names, rearrange a sentence without changing the modifier’s target, use different whole numbers with the same structural relationship, replace one material with another while keeping the relevant variables controlled, or put a needed clue in a different paragraph. If your method changes merely because the surface changed, you were remembering a picture of the example rather than its mechanism.
A useful Version B changes exactly one controlling feature. The discipline of changing one feature prevents a muddled comparison. After making the change, complete the sentence, “The answer changes because…”. If you cannot name the causal or logical difference, the pair is not yet teaching you anything. Revise it until the difference is visible. This activity is especially valuable for rules with boundaries, because it shows both where the rule works and where another idea must take over.
A useful Version C teaches sufficiency. Remove a value, condition, referent, observation or comparison that the answer requires, but keep enough context for the question to look tempting. Then state exactly what can still be concluded and exactly what cannot. If additional information would make the question answerable, name it. The goal is not to refuse every difficult question. The goal is to distinguish a demanding inference from an impossible one.
Accuracy before speed, then speed with evidence
Do not time the first stage of repair. Work slowly enough to carry out the full routine and produce proof-quality answers. Record which step feels effortful. After three accurate sessions, begin timing small mixed sets, but preserve a separate checking interval. This order matters: speed is repeated decision-making, so practising fast guesses makes the wrong decision more automatic. Practising accurate decisions first gives speed a reliable path to follow.
Track two measures rather than one. The first is answer accuracy. The second is decision accuracy: did you identify the correct target, relationship, controlled variable, evidence gap or boundary even if a later calculation or spelling slip occurred? A learner whose decision accuracy is improving is building a durable method. A learner who gets occasional answers right while decision accuracy remains low is still depending on recognition and luck. Use the two measures to choose the next practice task.
During a timed paper, use a two-pass system. On the first pass, solve questions whose task and evidence chain are clear. Mark uncertain items with a small symbol and move on before one question consumes disproportionate time. On the second pass, diagnose the uncertainty: missing knowledge, missing information, competing interpretations, or an unchecked calculation. Give each type a specific response. This is more efficient than rereading the whole question repeatedly without knowing what you are looking for.
End every practice set with one retrieval prompt: write the central rule from memory, one example where it works, one near-miss where it does not, and one checking question you will ask next time. This four-part exit record takes only a few minutes, yet it converts completed work into a reusable mental tool. On the following day, reconstruct the record before looking at it. The delay shows whether the idea has become available independently or remains tied to the page.
Examination control
1. Find of. Partitive phrases usually reveal the noun whose quantity is being discussed.
2. Name the target. State silently whether the percentage measures a substance, one object or plural members.
3. Check the real subject. Distinguish “the percentage of…” from “a percentage of…”.
4. Use a pronoun substitute. It is versus they are can expose the intended number quickly.
5. Protect meaning. Choose wording that makes a collective group or its members unambiguous.
6. Reread the whole sentence. Agreement belongs to the complete clause, not an isolated number.
A strong examination routine is deliberately modest. It does not ask you to become brilliant in the final minute. It asks you to expose one hidden assumption, one missing unit, one unsupported word or one untested condition before it costs a mark. When time is short, check the exact sentence that carries the conclusion.
A seven-day repair cycle
Day 1 — Diagnose
Complete five short items and mark the exact point at which your reasoning became too broad. Do not merely write “careless”. Name the missing distinction.
Day 2 — Contrast
Place a correct and an almost-correct answer side by side. Underline the word, number or condition that separates them.
Day 3 — Explain
Teach the central rule to an imaginary younger pupil without using the worked example. If you need the original wording, the rule is not yet portable.
Day 4 — Mix
Combine this topic with two unrelated question types. Mixed practice trains recognition because no heading tells you which method to use.
Day 5 — Delay
Return to three earlier items without notes. Reconstruct the routine and record which step was forgotten.
Day 6 — Time
Complete a short set under a calm time limit, then spend a separate minute on conclusion checks. Keep solving time and checking time distinct.
Day 7 — Transfer
Create one new example, one counterexample and one explanation. A learner who can generate all three usually understands the boundary of the rule.
A quantity-agreement editing laboratory
Minimal-pair bank
Build ten pairs that keep the fraction constant but change the quantified noun from singular to plural: half of the route/routes, one-third of the box/boxes, and so on. Read each pair aloud, underline the noun that changes, and explain why the verb must follow it. Add two mass-noun examples so the bank does not become a simple visible-s rule.
Percentage-versus-the-percentage test
Write five pairs contrasting “X per cent of the…” with “The percentage of…”. In the first member, decide agreement from what is quantified. In the second, make percentage the singular subject. Explain the structural difference without saying only that one version sounds better.
Pronoun substitution clinic
Replace long quantified noun phrases with it or them, then choose the verb. Restore the original phrase and check whether the agreement remains. This technique is especially useful when adjectives, prepositional phrases or relative clauses make the subject hard to hear.
Collective-noun clarity
Collect five sentences using class, team, family or group. Revise each so the intended meaning is explicit: the organisation as one unit or the members as individuals. When school marking expectations favour one form, preserve that variety consistently while still understanding the meaning choice.
Cross-subject corpus
Find three quantity sentences in Science and three in Mathematics. Mark the fraction or percentage, the quantified noun and the verb. Decide whether the original writer uses agreement clearly. Rewrite any sentence in which a bare percentage hides what is being measured.
Error-generation task
Create four deliberately wrong sentences representing four different causes: percentage-as-singular shortcut, fraction-word shortcut, nearest-noun attraction and confusion between percentage as subject and percentage as quantifier. Diagnose each error before correcting it so the repair is tied to a mechanism.
Delayed mixed proofread
After two days, proofread a paragraph containing ordinary singular subjects, plural subjects, collective nouns and six partitive quantity phrases. Mark only the quantity phrases first; then check agreement. Record whether any mistake came from missing the noun, misclassifying its number or misunderstanding the sentence’s meaning.
For parents and tutors
Ask the learner what the percentage is a percentage of before discussing the verb.
Use cake/cakes and water/bottles contrasts to show that the same number expression can take different agreement.
When a collective noun causes uncertainty, encourage a clearer rewrite instead of relying only on what sounds familiar.
Frequently asked questions
Does a percentage always take a singular verb?
No. Agreement normally follows what the percentage quantifies.
Why is “half of the books are” plural?
Books is plural, and half selects members from that plural set.
Why is “the percentage is” singular?
In that structure, percentage itself is the singular head subject.
Can I use a pronoun test?
Yes. It is and they are often reveal the intended number.
What is the quickest final check?
Name what is being quantified, then match the verb to that noun or pronoun.
Next routes
Return to the complete volume directory to choose another precise learner problem, or revisit the original PSLE Learning Guide for the earlier foundation. For subject-specific support, continue through the verified PSLE English route on eduKateSG. These routes are for extending the mechanism, not for replacing your school’s instructions or the official examination document for your year.
Final reminder: The number tells how much or how many; the quantified noun tells the verb whether to be singular or plural.