O-Level Notes
O-Level English 1184 · The STAMP CARD framework
A-Worthy Education
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Take the diagnostic first. Your score tells you which sections to prioritise — each is linked in the scoring table. Your answers below save automatically in this browser, so you can close the page and come back.
This 50-sentence diagnostic identifies which STAMP CARD categories need your attention most. Most students are not uniformly weak across all nine categories — you have a specific profile. Spending 35 minutes here saves hours of unfocused revision later.
Identify and correct the one error in each sentence.
| No. | Sentence | Your Correction |
|---|
Finish all 50 first. The key stays hidden until you choose to reveal it.
| No. | Tag | Correction | Why |
|---|
Tally the number of correct answers in each row. The maximum for each category is shown in brackets; categories are tested unequally, so the totals differ.
| Tag | Category | Score | Priority Section |
|---|---|---|---|
| T | Tense (Q1, 11, 21, 22, 23, 24) | /6 | 3.1 Tense |
| S | Subject-Verb Agreement (Q2, 4, 12, 20, 26, 27, 28, 29) | /8 | 3.2 Subject-Verb |
| A1 | Articles (Q3, 30, 31) | /3 | 3.3 Articles |
| M | Match Pronouns (Q10, 32, 33, 34, 35) | /5 | 3.4 Pronouns |
| P | Prepositions (Q5, 15, 37, 38, 39, 40) | /6 | 3.5 Prepositions |
| C | Connectors (Q6, 16, 41, 42, 43) | /5 | 3.6 Connectors |
| A2 | Adjective / Adverb (Q7, 17, 44, 45, 46, 47) | /6 | 3.7 Word Form |
| R | Right Number (Q8, 14, 18, 48, 49) | /5 | 3.8 Right Number |
| D | Degree of Comparison (Q9, 19, 50) | /3 | 3.9 Comparison |
| — | Error-free sentences (Q13, 25, 36) | /3 | — |
Question counts per category are uneven because S and R are typically over-tested in exam passages.
How to interpret your scores
Each letter in STAMP CARD represents one category of grammar error tested in the O-Level editing question. Think of it like a bubble tea stamp card: go through the letters one by one for every numbered line, check each category, and stamp off errors as you find them until you collect all 8 corrections.
The framework provides nine categories to check on every numbered line. The exam includes eight errors in total across the passage, with two lines deliberately error-free. The framework letters are the categories you check; they do not map one-to-one onto the eight errors.
| Error Type | Quick Check Question | |
|---|---|---|
| S | Subject-Verb Agreement | Does the verb agree with the subject in number? |
| T | Tense | Is the verb in the correct tense? Check time markers. |
| A1 | Articles | Is ‘a’, ‘an’ or ‘the’ used correctly? Based on sound, not spelling. |
| M | Match Pronouns | Does the pronoun match its antecedent in number, gender and form? |
| P | Prepositions | Is the correct preposition used? Check fixed phrases and collocations. |
| C | Connectors | Is the linking word logically correct? ‘Although’ and ‘but’ cannot be used together. |
| A2 | Adjective / Adverb (Word Form) | Is it describing a noun (adjective) or a verb / adjective / adverb (adverb, usually -ly)? |
| R | Right Number | Is the noun singular or plural? Does the quantifier match? |
| D | Degree of Comparison | Comparative or superlative correct? An adjective takes either -er/-est or more/most, never both. |
Note on the two A’s
STAMP CARD contains two A categories. A1 is Articles (a, an, the). A2 is Adjective / Adverb (word form). They test entirely different things — do not confuse them. When working through the checklist, treat them as two separate stops.
Technique: Use STAMP CARD as a checklist for every numbered line. Read the passage once for meaning first, then check each letter in order, prioritising T, S, A2.
Thought Process — Why T, S, A2
T, S and A2 errors appear in almost every exam passage because they involve the most common grammar rules in English: tense consistency, agreement, and word class. Starting with these three means you will catch the majority of errors efficiently before spending time on the less frequent categories. Treat T, S and A2 as the first pass over every line. (Note: this is A2, word form — not A1, articles, which is tested less often.)
The nine categories do not appear equally often. The table below ranks them by approximate frequency across recent 1184 editing passages. Use it to allocate revision time.
| Tag | Category | Frequency | Revision Priority |
|---|---|---|---|
| T | Tense | Very high | Highest priority. Almost every passage tests at least one. |
| S | Subject-Verb Agreement | Very high | Highest priority. Often tested twice in a single passage. |
| A2 | Adjective / Adverb | High | Highest priority. Almost as common as T and S. |
| P | Prepositions | High | Drill the high-yield collocations (see 3.5). |
| M | Match Pronouns | Moderate | Common in passages with people or specific noun groups. |
| C | Connectors | Moderate | Watch for paired connectors and correlative pairs. |
| R | Right Number | Moderate | Watch for uncountable nouns and determiners. |
| A1 | Articles | Lower | Tested less often but easy to spot when present. |
| D | Degree of Comparison | Lower | Tested less often. Identifiable on sight by -er, -est, more, most. |
Revision implication
Spend roughly 60 per cent of your revision time on the three highest-priority categories — T, S and A2. They account for the majority of errors in a typical passage. Divide the remaining time across the other six.
Each error type is explained with the full grammar rule, all known sub-patterns, worked examples, and annotated thought-process boxes that explain how an expert reader identifies and corrects each error.
The tense of every verb must match the time frame the passage is set in. Narrative and recount passages use the past tense. Informative and factual passages use the present tense. Your first read of the passage exists to establish the tense.
| Time Marker | Signals | Expected Tense |
|---|---|---|
| yesterday, last year, in 2010, once, at that time, in the past | Past events — completed | Past Simple throughout |
| every day, now, currently, generally, always, nowadays | Present facts or habits | Present Simple throughout |
| by 2030, in the future, next year, soon, eventually | Predictions or future states | will + base verb |
The three high-yield tenses. Past Simple, Present Simple and Present Perfect are the only tenses heavily tested in editing. Learn these three thoroughly before the others.
| Tense | Form | When to Use | Example |
|---|---|---|---|
| Past Simple | verb+ed / irregular | Completed action; narrative passages. | She walked. |
| Present Simple | verb / verb+s | Habits, routines, general truths, factual passages. | She walks. |
| Present Perfect | have/has + p.p. | Past action with continuing relevance. Tested via clash with specific past time markers. | She has walked. |
For the full twelve-tense reference, see Appendix A.
Worked Example 1
She walk into the lab yesterday.→She walked into the lab yesterday.
Time marker: yesterday — signals past. Main verb walk is the base form. Correct to Past Simple: walked.
Worked Example 2
I have seen that film last night.→I saw that film last night.
Last night is a specific past time, which locks the event in the past. Present Perfect cannot co-exist with it. Replace with Past Simple.
Worked Example 3
The problem is compounding.→The problem is compounded.
Ask: is the subject doing an action, or in a condition? The problem is in a worsened state, so the past participle is required, not the present participle.
Thought Process — Present vs Past Participle After ‘To Be’
When you see is/was/are/were followed by a verb form, ask: is the subject doing something, or in a condition?
The problem is compounding implies the problem is actively compounding something. That is not the intended meaning — the problem has been made worse. Therefore: compounded.
Thought Process — Present Perfect vs Past Simple
If a specific past time marker and have/has appear together in one clause — that is a T error.
A singular subject takes a singular verb. A plural subject takes a plural verb. The exam places extra words between the subject and the verb to make the wrong noun look like the subject. Your job is to strip those words out.
Worked Example 1
The average age of caregivers are about 62.→The average age of caregivers is about 62.
Cover of caregivers. Remaining subject: the average age — singular.
Worked Example 2
Each of the boys have a book.→Each of the boys has a book.
Each is an indefinite pronoun and is always singular.
Worked Example 3
Neither the teacher nor the students was present.→Neither the teacher nor the students were present.
Compound subject with nor — apply the proximity rule. Closest subject: students (plural).
Thought Process — The Proximity Trap
Passages often place a plural noun immediately before the verb when the actual subject is singular. The nearest noun is the one the eye settles on, and that is the trap.
A practical method: cover the words between of (or a similar preposition) and the verb with your finger, then read what remains. The true subject becomes clear.
| Pattern | Rule | Example |
|---|---|---|
| Collective nouns | group, team, committee, family — singular in formal writing | The committee has decided. |
| Indefinite pronouns | each, every, either, neither, no one, someone, everyone — always singular | Everyone has submitted. |
| ‘A number of’ vs ‘The number of’ | A number of = plural; The number of = singular | A number of students were late. |
| Or / nor | Verb agrees with the subject closest to it | Neither he nor they were informed. |
| Relative clauses | Verb agrees with the noun the clause refers to | It is the students who are responsible. |
The articles are a, an and the. The key distinction for a vs an is the sound the following word begins with — not the letter.
| Article | When to Use | Examples |
|---|---|---|
| a | Singular countable nouns beginning with a consonant sound. | a book, a university (/j/), a one-way street (/w/), a European (/j/) |
| an | Singular countable nouns beginning with a vowel sound. | an apple, an hour (silent h), an honest man, an MBA (/em/) |
| the | Specific, already mentioned or uniquely identifiable nouns. Before superlatives. | the book I mentioned, the tallest building, the sun |
| no article | Plural countable nouns used generally; uncountable nouns generally; proper nouns. | Dogs are loyal. Water is essential. Singapore is small. |
Thought Process — Sound, Not Spelling
Rule: say the word aloud in your head. Whatever sound comes first determines the article.
Worked Example 1
She is a honest person.→She is an honest person.
The H in honest is silent, so the first sound is a vowel.
Worked Example 2
He is an honest and a hardworking employee.→He is an honest and hardworking employee.
Both adjectives modify the same noun, so only one article is needed.
Worked Example 3
She is interested in a environment.→She is interested in the environment.
The environment is a specific, uniquely identifiable concept.
A pronoun must agree with its antecedent in number, gender and person, and must be in the correct form for its role: subject, object, possessive or reflexive.
| Person | Subject | Object | Possessive | Reflexive |
|---|---|---|---|---|
| 1st singular | I | me | my / mine | myself |
| 2nd sing./plural | you | you | your / yours | yourself / yourselves |
| 3rd singular (m) | he | him | his | himself |
| 3rd singular (f) | she | her | her / hers | herself |
| 3rd singular (n) | it | it | its | itself |
| 1st plural | we | us | our / ours | ourselves |
| 3rd plural | they | them | their / theirs | themselves |
Worked Example 1 — Number
This patients are grateful for the subsidies.→These patients are grateful for the subsidies.
This is for singular nouns; these is for plural.
Worked Example 2 — Subject / Object Form
Me and my friend went to the library.→My friend and I went to the library.
Remove my friend: “Me went to the library” — obviously wrong. Convention: put yourself last.
Worked Example 3 — Reflexive Misuse
Please contact myself if you have questions.→Please contact me if you have questions.
Reflexive pronouns are only valid when subject and object are the same person.
Thought Process — Subject vs Object Form
The removal test: “The teacher gave the award to John and I.” → Remove John: “gave the award to I” → wrong → use me.
The preposition rule: after any preposition (to, for, with, between, from, at, by, of) always use the object form. Never I, he, she, we, they after a preposition.
Thought Process — Singular ‘They’
Indefinite pronouns (everyone, someone, anyone, each, every) are grammatically singular but refer to people of unknown or mixed gender. Modern formal English accepts singular they/their: “Everyone must bring their own pen.”
Caution: the verb still follows the singular antecedent (everyone has, not everyone have). In the exam, do not mark singular they as an error.
A preposition error occurs when the wrong preposition is used with a verb, adjective or noun. These are fixed phrases (collocations): they are settled by usage rather than by rule, so each one has to be learnt individually.
Thought Process — Why Prepositions Cannot Be Guessed
Consider afflicted with. Why with and not by or from? There is no logical grammar reason — the word simply collocates with with. Reasoning from meaning alone will not produce the right answer.
Strategy: every time you meet a preposition error in practice, add the phrase to a personal list. A list built from your own mistakes is the most efficient way to revise this category.
Entries marked ★ are recurrent high-yield phrases. Learn these first.
Worked Examples
She is good in Mathematics.→good at — fixed phrase for a subject or skill.
He insisted at going alone.→insisted on — insist on + gerund.
She is afflicted through chronic illness.→afflicted with — no other preposition is idiomatic.
A connector error occurs when the wrong linking word is used, or when two conflicting connectors appear together. The connector must accurately reflect the logical relationship between the clauses it joins.
| Relationship | Connectors | Example |
|---|---|---|
| Contrast | but, however, yet, although, even though, despite, nevertheless | She studied hard, but she failed. |
| Cause | because, since, as, due to, owing to | She passed because she studied. |
| Result | so, therefore, thus, hence, consequently | She studied hard; therefore, she passed. |
| Addition | and, furthermore, moreover, in addition | She studied hard and revised her notes. |
| Condition | if, unless, provided that, as long as | She will pass if she studies. |
| Concession | although, even though, while, whereas | Although unpopular, it was necessary. |
Thought Process — ‘Although’ + ‘But’ Cannot Co-exist
This is the most commonly tested C error. Although signals concession; but also signals contrast. English allows only one connector per logical relationship.
The same logic applies to because + so. One logical relationship → one connector.
Thought Process — Comma Splice with ‘However’
However is a conjunctive adverb, not a coordinating conjunction. It cannot join two independent clauses with only a comma. “She studied hard, however she failed.” is a comma splice. Three fixes:
The same rule applies to therefore, moreover, furthermore, consequently, nevertheless.
| Correct Pair | Common Error |
|---|---|
| not only … but also | not only … and also |
| neither … nor | neither … or |
| either … or | either … nor |
| both … and | both … as well as |
| whether … or | whether … nor |
| as … as | as … than |
| so … that | so … which |
Worked Examples
Although he was tired, but he continued working.→Although he was tired, he continued working.
He is not only hardworking, and also creative.→not only … but also
Despite he was ill, he came to school.→Despite being ill, he came to school. — Despite takes a noun or gerund, not a clause.
An adjective modifies a noun. An adverb modifies a verb, adjective or another adverb. This is the most frequently tested error type. The error is almost always an adjective used where an adverb is needed.
Worked Examples
He spoke confident in front of the class.→confidently — modifies the verb spoke.
… unable to cope mentally and physical …→physically — modifies cope, and must match mentally in parallel structure.
Her improve was remarkable.→improvement — the subject of a sentence must be a noun.
| Noun | Verb | Adjective | Adverb |
|---|---|---|---|
| beauty | beautify | beautiful | beautifully |
| care | care | careful / careless | carefully / carelessly |
| efficiency | — | efficient | efficiently |
| confidence | — | confident | confidently |
| significance | signify | significant | significantly |
| success | succeed | successful | successfully |
| necessity | necessitate | necessary | necessarily |
| fluency | — | fluent | fluently |
| frequency | — | frequent | frequently |
| health | — | healthy | healthily |
Thought Process — Confusable Adjective Pairs
Thought Process — Verb vs Noun Confusables
Singapore convention: Singapore follows British spelling. Use practise (verb) and practice (noun).
R covers two related error types: (1) a noun in the wrong number; (2) a determiner or quantifier that does not match its noun. Do not confuse R with S. S is about the verb not agreeing with the subject. R is about the noun itself being in the wrong form, or its determiner being wrong.
Thought Process — Countable vs Uncountable
A countable noun can be counted: one book, two books. An uncountable noun cannot: information, advice, water.
“Many informations” is wrong because information is uncountable. Correct: much information.
| Determiner | Use With | Common Error | Correct |
|---|---|---|---|
| many | Countable plural only | many information | much information |
| much | Uncountable only | much students | many students |
| few / a few | Countable plural | few time | little time |
| little / a little | Uncountable | little students | few students |
| fewer | Countable plural | less books | fewer books |
| less | Uncountable | less students | fewer students |
| number of | Countable | A number of students was late. | A number of students were late. |
| amount of | Uncountable | amount of students | number of students |
| this / that | Singular nouns | this patients | these patients |
| these / those | Plural nouns | these information | this information |
| every / each | Singular countable | every students | every student |
Thought Process — Amount vs Number
amount → uncountable: a large amount of water. number → countable plural: a large number of students.
Memory aid: if you can count it, use number. If you can only measure it, use amount.
Worked Examples
The report contained many informations.→much information — both noun and determiner must change.
A large amount of residents attended.→A large number of residents — residents is countable.
a single criteria→a single criterion — criteria is the plural.
Uncountable nouns (no plural form): information, advice, furniture, equipment, luggage, knowledge, news, progress, research, traffic, weather, work, music, money, food, education, evidence, homework, accommodation, behaviour, damage, harm, luck, scenery, travel.
| Singular | Plural | Singular | Plural |
|---|---|---|---|
| datum | data | analysis | analyses |
| criterion | criteria | basis | bases |
| phenomenon | phenomena | hypothesis | hypotheses |
| medium | media | curriculum | curricula |
D errors involve using the wrong degree of comparison, or forming it incorrectly by combining both the -er/-est suffix and the word more/most on the same adjective. Three degrees: positive (base), comparative (two), superlative (three or more).
| Adjective Type | Positive | Comparative | Superlative | Note |
|---|---|---|---|---|
| One syllable | tall, old | taller, older | tallest, oldest | Double final consonant if short vowel + consonant: big → bigger |
| One syllable -e | wide, safe | wider, safer | widest, safest | Add -r/-st only |
| Two syllables -y | happy, easy | happier, easier | happiest, easiest | Change -y to -i |
| Two+ syllables | beautiful | more beautiful | most beautiful | Never add -er/-est |
| Irregular | good, bad, far | better, worse, further | best, worst, furthest | Memorise. Never add -er/-est or more/most |
Thought Process — How Many Things Are Being Compared?
Double comparative / superlative: if you see both more and -er on the same adjective, or both most and -est — that is always an error.
Worked Examples
She is more taller than her sister.→taller — double comparative.
This is the most easiest question.→easiest — double superlative.
He is the most intelligent of the two.→the more intelligent — of the two signals exactly two.
Work through this in three stages: attempt the clean passage on your own; check against the revealed version, where the candidate error words are underlined; then compare against the annotated key, including the common wrong corrections students typically write.
| Line | Passage | Your Answer |
|---|
The underlined words are the candidate error sites. Verify whether your corrections targeted these words. If you corrected a different word, the issue is your diagnostic — you flagged the wrong line position.
| Line | Passage with Errors Marked |
|---|
The Common Wrong Correction column records the mistake students most frequently make on that line. Even if you got the right answer, read this column.
| Line | Correction | Tag | Explanation | Common Wrong Correction |
|---|
Thought Process — Approaching Error-Free Lines
Lines 7 and 9 are error-free. Two lines are always correct in every exam passage. When you have gone through all nine STAMP CARD letters on a line and found nothing, tick it immediately and move on. Students who expect every line to have an error will manufacture one on the correct lines.
The high-frequency word pairs that the exam exploits. These look or sound similar but mean different things, so they are easy to mix up under time pressure. Revise this single page in the final week before the exam.
| Pair | Meaning | Example |
|---|---|---|
| economic | relating to the economy | The economic outlook is poor. |
| economical | thrifty, cost-saving | This car is economical. |
| historic | important in history | A historic speech by the Prime Minister. |
| historical | relating to the past | A historical novel set in 1920s Singapore. |
| classic | of high quality, traditional | A classic film from the 1950s. |
| classical | ancient Greece/Rome, or traditional art forms | Classical music; classical literature. |
| sensitive | easily affected | Sensitive skin; a sensitive topic. |
| sensible | showing good judgement | A sensible decision; sensible shoes. |
| literal | exact, word-for-word | A literal translation. |
| literary | relating to literature | A literary device. |
| considerable | large in size or amount | A considerable sum of money. |
| considerate | kind, thoughtful of others | A considerate colleague. |
| imaginary | not real | An imaginary friend. |
| imaginative | creative | An imaginative writer. |
| industrial | relating to industry | An industrial estate. |
| industrious | hardworking | An industrious student. |
| Word | Part of Speech | Example |
|---|---|---|
| advise | verb | I advise you to study. |
| advice | noun | She gave me good advice. |
| affect | verb (to influence) | The weather affects mood. |
| effect | noun (a result) | The effect was clear. |
| practise | verb (British) | I practise piano daily. |
| practice | noun (British) | Daily practice is essential. |
| license | verb (British) | The shop is licensed to sell alcohol. |
| licence | noun (British) | She lost her driving licence. |
| prophesy | verb (to predict) | The seer will prophesy the outcome. |
| prophecy | noun (a prediction) | The prophecy came true. |
| breathe | verb | Remember to breathe deeply. |
| breath | noun | Take a deep breath. |
| lose | verb | Do not lose your way. |
| loose | adjective (not tight) | The screw is loose. |
Singapore convention
Singapore follows British spelling. Use practise (verb) / practice (noun), licence (noun) / license (verb). American spellings are marked wrong in 1184.
These adverbs do not take -ly. Adding -ly either produces a non-word or a word with a different meaning.
| Word | Correct Use | Trap Word |
|---|---|---|
| hard | work hard (with great effort) | hardly = almost not at all |
| fast | run fast | fastly is not a word |
| late | arrive late | lately = recently |
| high | fly high | highly = to a great degree |
| near | stand near | nearly = almost |
| deep | dig deep | deeply = profoundly |
| Pair | Use With | Example |
|---|---|---|
| fewer | countable plural | Fewer students passed this year. |
| less | uncountable | Less time is available. |
| many | countable plural | Many people attended. |
| much | uncountable | Much effort was wasted. |
| number of | countable plural | A number of students were late. |
| amount of | uncountable | A small amount of water remained. |
| this | singular noun | This student is here. |
| these | plural noun | These students are here. |
| Singular | Plural | Singular | Plural |
|---|---|---|---|
| datum | data | analysis | analyses |
| criterion | criteria | basis | bases |
| phenomenon | phenomena | hypothesis | hypotheses |
| medium | media | curriculum | curricula |
Thought Process — The Confusables Trap
These pairs are confused often enough to be worth checking on sight. If a word from this chapter appears in a passage, slow down and confirm it is the correct member of the pair. Most errors come from this list rather than from obscure rules.
The editing question is worth 8 marks in Paper 1 and should take no more than 10 minutes. Pacing matters more than any single grammar tip.
| Stage | Time | What to Do |
|---|---|---|
| First read | 2 min | Read the passage for meaning. Identify the tense. Do not correct yet. Write S-T-A-M-P-C-A-R-D in the margin. |
| Line-by-line pass | 6 min | About 36 seconds per numbered line. Run the checklist. Stop the moment you find one error. |
| Review pass | 1.5 min | Re-check the two lines you marked ‘no error’. Re-check any line where you were uncertain. |
| Buffer | 0.5 min | Reserved for any line you flagged for return. |
Timing self-test
During your last fortnight of revision, attempt editing passages with a stopwatch. If you cannot finish within 10 minutes, the problem is your method rather than your grammar. Practise the procedure before learning more rules.
The practice answers are in a separate booklet
To keep you from glancing at answers while you work, all worked solutions to the practice questions in Chapter 3 (3.1–3.9) are published in a companion document: Editing — Answer Key.
Attempt every practice question on your own first. Mark your work only after you have completed a full set. Each answer in the companion booklet gives the correction and a one-line reason, cross-referenced to the relevant section here.
The three tenses tested most often in 1184 editing are Past Simple, Present Simple and Present Perfect (see 3.1). This appendix lists all twelve for completeness.
| Tense | Form | When to Use | Example |
|---|---|---|---|
| Present Tenses | |||
| Present Simple | verb / verb+s | Habits, routines, general truths. | She walks. |
| Present Continuous | am/is/are + -ing | Action happening right now. | She is walking. |
| Present Perfect | have/has + p.p. | Past action with current relevance. | She has walked. |
| Present Perfect Cont. | have/has + been + -ing | Ongoing action from past until now. | She has been walking. |
| Past Tenses | |||
| Past Simple | verb+ed / irregular | Completed action; narrative passages. | She walked. |
| Past Continuous | was/were + -ing | Ongoing past action; background. | She was walking. |
| Past Perfect | had + p.p. | Earlier of two past events. | She had walked. |
| Past Perfect Cont. | had + been + -ing | Ongoing action before another past event. | She had been walking. |
| Future Tenses | |||
| Future Simple | will + base | Prediction, promise, decision. | She will walk. |
| Future Continuous | will + be + -ing | In progress at a future moment. | She will be walking. |
| Future Perfect | will + have + p.p. | Completed before a future point. | She will have walked. |
| Future Perfect Cont. | will + have + been + -ing | Ongoing up to a future point. | She will have been walking. |
Thought Process — Why Only Three Tenses Matter for Editing
1184 editing passages are written in either present tense (factual) or past tense (narrative). The exam tests whether you can detect a verb that violates the established tense. In practice, three tenses do almost all the work: Past Simple dominates narrative passages, Present Simple dominates factual passages, and Present Perfect appears as a trap. The full table is for wider reference — not for memorisation.