3. Verb Types & Classification

3.1 Transitive vs Intransitive Verbs

A transitive verb needs a direct object to complete its meaning (She wrote a letter — "a letter" is the object). An intransitive verb makes complete sense without one (The baby slept). The exam trap is that many common verbs are transitive in one sense and intransitive in another, or are used with the wrong preposition/object structure.

Verbs commonly misused (correct usage shown):

Verb	Common Error	Correct Use
lay / lie	He lay the file on the table.	He laid the file on the table. (lay = transitive, "to put something down"; lie = intransitive, "to recline")
rise / raise	Prices raised sharply last month.	Prices rose sharply last month. (rise = intransitive; raise = transitive, needs an object: "The company raised prices.")
reach	We reached to the venue on time.	We reached the venue on time. (reach is transitive; no preposition needed before a place)
discuss	Let us discuss about this issue.	Let us discuss this issue. (discuss is transitive; never followed by "about")
marry	He married with her last year.	He married her last year. (marry is transitive; no "with")
enter	She entered into the room.	She entered the room. (physical entry is transitive; "enter into" is reserved for abstract agreements, e.g. "enter into a contract")
resemble	He resembles to his father.	He resembles his father. (transitive; no preposition)
answer	He answered to my question.	He answered my question. (transitive when the object is the question itself)
attain	She attained to success.	She attained success. (transitive; no preposition)
comprise	The committee is comprised of five members. (widely used but debated)	The committee comprises five members. (comprise is transitive and already means "is made up of"; avoid "is comprised of" in formal exams)
appear	The results appeared to be published.	Depends on context — "appear" is intransitive: The results appeared on the notice board.
happen	This incident was happened yesterday.	This incident happened yesterday. (intransitive; never used in the passive voice)
occur	The accident was occurred at noon.	The accident occurred at noon. (intransitive; no passive form)
arise	A problem was arisen suddenly.	A problem arose suddenly. (intransitive; no passive form)
die	He was died last year.	He died last year. (intransitive; no passive form)
fall	The vase was fallen off the shelf.	The vase fell off the shelf. (intransitive; no passive form)
apologize	He apologized me for the delay.	He apologized to me for the delay. (intransitive; requires "to" before the person)
object	She objected the new rule.	She objected to the new rule. (intransitive; requires "to" before the thing objected to)
complain	He complained the manager about the delay.	He complained to the manager about the delay. (intransitive; "to" before a person, "about" before the topic)
explain	Please explain me the process.	Please explain the process to me. (transitive with the thing explained as direct object; the person takes "to")

3.2 Regular vs Irregular Verbs

Regular verbs form their past simple and past participle by adding -ed (or -d/-ied for spelling variants): walk → walked → walked, study → studied → studied, stop → stopped → stopped.

Irregular verbs change form unpredictably: go → went → gone, cut → cut → cut, sing → sang → sung. Because there's no rule to derive them, they must be memorized — see the full reference table in Section 4, now expanded to more than two hundred verbs. Exam-setters frequently test irregular verbs by inserting the wrong principal part (using the past simple where a past participle is needed, or vice versa) — this is one of the most common and most "free" marks available if you know the table cold.

A note on regular-verb spelling traps that examiners also test alongside irregular forms:

• Verbs ending in a single stressed vowel + consonant usually double the final consonant before -ed: stop → stopped, plan → planned, permit → permitted. A common error is leaving the consonant single: stoped, planed (both wrong).
• Verbs ending in a consonant + -y change the -y to -i before adding -ed: study → studied, carry → carried. Verbs ending in a vowel + -y keep the -y: play → played, not "plaied."
• Verbs already ending in -e simply add -d: hope → hoped, not "hopeed."

3.3 Finite vs Non-Finite Verbs

A finite verb shows tense, person, and number, and can stand as the main verb of an independent clause (She writes, They wrote, He is writing). A non-finite verb does not show tense and cannot form a sentence by itself — it includes infinitives (to write), gerunds (writing, used as a noun), and participles (written, writing, used as adjectives or in verb phrases).

• Finite: He completed the report.
• Non-finite (infinitive): He wants to complete the report.
• Non-finite (gerund): Completing the report took two hours.
• Non-finite (participle): The report, completed on time, impressed the client.

Common exam trap: using a non-finite form where a finite verb is required, or vice versa.

• Wrong: He go to office daily to completing his pending tasks.
• Fix: He goes to office daily to complete his pending tasks. (the main clause needs a finite verb "goes"; purpose is expressed with the infinitive "to complete," not a gerund)

A second common trap — a sentence with no finite verb at all (a sentence fragment mistaken for a complete sentence):

• Wrong: The manager, having reviewed all the applications carefully before the deadline. (this is a participial phrase, not a complete sentence — there is no finite verb)
• Fix: The manager reviewed all the applications carefully before the deadline. / Having reviewed all the applications, the manager shortlisted five candidates. (the participial phrase needs an accompanying finite clause to complete the sentence)

3.4 Auxiliary Verbs: Primary vs Modal

Primary auxiliaries — be, do, have — help form tenses, questions, negatives, and the passive voice, and they also change form with tense and subject (is/am/are/was/were, do/does/did, has/have/had).

Modal auxiliaries — can, could, may, might, shall, should, will, would, must, ought to, need, dare — express ability, possibility, permission, obligation, or necessity. Unlike primary auxiliaries, modals never change form for person or number (no "he cans"), and they are always followed by the base form of the verb (except "ought to," which takes the infinitive with "to").

Exam trap — double modal or modal + wrong form:

• Wrong: He can sings well. Fix: He can sing well. (never add -s after a modal)
• Wrong: She must to finish the work today. Fix: She must finish the work today. ("must" is directly followed by the base form, no "to")
• Wrong: You should must complete the form. Fix: You must complete the form. (only one modal is allowed per verb phrase)
• Wrong: He might can attend the interview tomorrow. Fix: He might be able to attend the interview tomorrow. (two modals cannot be stacked; use a modal-equivalent phrase like "be able to" for the second idea)

3.5 Stative vs Dynamic Verbs

Dynamic verbs describe actions and can be used in continuous (progressive) tenses: run, eat, write, build. Stative verbs describe states — thoughts, emotions, senses, possession, or relationships — and are not normally used in continuous forms because a "state" is not something you can be "in the middle of doing."

A list of 30 common stative verbs, with example sentences:

1. know — I know the answer. (not "am knowing")
2. believe — She believes in hard work.
3. understand — He understands the concept clearly.
4. realize — We realize the importance of this project.
5. remember — I remember his name now.
6. forget — She forgets small details often.
7. recognize — He recognizes the voice instantly.
8. suppose — I suppose you are right.
9. doubt — She doubts his intentions.
10. agree — They agree with the proposal.
11. disagree — He disagrees with the policy.
12. want — She wants a promotion this year.
13. need — We need more resources for this task.
14. wish — He wishes for a better outcome.
15. desire — They desire peace and stability.
16. prefer — I prefer tea over coffee.
17. love — She loves classical music.
18. hate — He hates being late.
19. like — We like the new office layout.
20. dislike — She dislikes loud noises.
21. own — They own two properties in the city.
22. possess — He possesses great patience.
23. belong — This land belongs to the government.
24. contain — The bottle contains two litres of water.
25. consist — The exam consists of three sections.
26. appear (meaning "seem") — She appears confident about the interview.
27. seem — The plan seems reasonable.
28. resemble — He resembles his grandfather.
29. cost — The new machine costs a lot.
30. weigh (meaning "have a weight of") — The parcel weighs two kilograms.

Note on dual-nature verbs: some of these — think, have, weigh, appear, taste, see — can be dynamic in a different sense. "I think you're right" (stative, opinion) vs "I'm thinking about it" (dynamic, mental process in progress). "He has a car" (stative, possession) vs "He is having lunch" (dynamic, an activity). "This soup tastes salty" (stative, a quality) vs "The chef is tasting the soup" (dynamic, an action of sampling). "She sees the point" (stative, understanding) vs "She is seeing a specialist next week" (dynamic, meeting/consulting). Exams sometimes test this exact distinction, so read the full sentence for meaning rather than reacting to the verb alone.

3.6 Phrasal Verbs

A phrasal verb combines a verb with a particle (preposition and/or adverb) to create a meaning distinct from the individual words. These are heavily tested in one-word-substitution and fill-in-the-blank questions. The list below has been expanded to more than ninety entries, grouped loosely by everyday theme so that related meanings sit near each other and are easier to retain as clusters rather than as one undifferentiated alphabetical list.

Daily life and general use

Phrasal Verb	Meaning	Example Sentence
bring up	to raise a topic / to raise a child	She brought up the issue during the meeting.
call off	to cancel	The organizers called off the event due to rain.
carry out	to perform/execute	The team carried out the instructions carefully.
come across	to find by chance	I came across an old photograph yesterday.
do away with	to eliminate	The new policy did away with unnecessary paperwork.
draw up	to prepare a document	The lawyer drew up the contract overnight.
fall through	to fail to happen	Our travel plan fell through at the last minute.
get along with	to have a good relationship	He gets along with all his colleagues.
give up	to stop trying / to quit	She gave up smoking last year.
go through	to experience / to examine carefully	He went through the entire document before signing.
hand in	to submit	Please hand in your assignments by Friday.
hold on	to wait	Hold on a moment, I'll check the file.
keep up with	to maintain pace	It's hard to keep up with the changing rules.
look after	to take care of	She looks after her elderly parents.
look into	to investigate	The police are looking into the matter.
make up for	to compensate	He worked overtime to make up for the delay.
pass away	to die	Her grandfather passed away last month.
put off	to postpone	They put off the meeting until next week.
put up with	to tolerate	I can't put up with this noise anymore.
run out of	to exhaust a supply	We ran out of printer paper this morning.
show up	to arrive/appear	He showed up late for the interview.
take after	to resemble (a relative)	She takes after her mother in temperament.
turn up	to arrive unexpectedly	An old friend turned up at the reunion.
break down	to stop functioning / to lose emotional control	The old bus broke down on the highway.
bring about	to cause	The reforms brought about major changes.
carry on	to continue	Despite the setback, she carried on with her studies.
cut down on	to reduce	He is trying to cut down on sugar.
deal with	to handle	The manager knows how to deal with complaints.
drop out	to quit a course	He dropped out of college after one year.
figure out	to understand/solve	She figured out the solution quickly.
get over	to recover from	It took her weeks to get over the illness.
hold up	to delay	Traffic held up the delivery van.
look forward to	to anticipate with pleasure	We look forward to hearing from you.
point out	to indicate	The teacher pointed out several errors.
think over	to consider carefully	Please think over the offer before deciding.
wear out	to become unusable through use	His old shoes finally wore out.
work out	to exercise / to be resolved successfully	Everything worked out well in the end.
calm down	to become less agitated	She calmed down after a few deep breaths.
catch up on	to bring oneself up to date	He spent the weekend catching up on sleep.
clean up	to tidy	The volunteers cleaned up the park on Sunday.
cheer up	to become or make happier	A short walk always cheers her up.
clear up	to become clear (weather/misunderstanding)	The confusion was cleared up after the meeting.
come up with	to produce an idea or plan	She came up with a clever solution.
get through	to survive/complete a difficult period	They got through the exams despite the pressure.
grow up	to become an adult	He grew up in a small village near Nashik.
look up to	to admire	Young engineers look up to her for guidance.
put down	to write something / to suppress	He put down his thoughts in a notebook.
run into	to meet by chance	I ran into my old teacher at the market.
settle down	to become calm and stable	After years of travel, they settled down in Pune.
take up	to begin a hobby or activity	She took up painting during the lockdown.
turn out	to result in a particular way	The plan turned out better than expected.
wake up	to stop sleeping	He wakes up at five every morning.

Business and formal / workplace use

Phrasal Verb	Meaning	Example Sentence
set up	to establish	They set up a new branch in Chennai.
take over	to assume control	She took over as manager last week.
stand for	to represent	NGO stands for Non-Governmental Organization.
put across	to communicate clearly	He put across his ideas convincingly.
call for	to require	This situation calls for immediate action.
roll out	to launch officially	The company rolled out its new app nationwide.
scale up	to increase in size or extent	The startup plans to scale up its operations next year.
lay off	to dismiss employees, usually for economic reasons	The firm laid off two hundred workers during the slowdown.
sign off on	to give formal approval	The director signed off on the revised budget.
draw on	to make use of a resource	The report draws on data from three separate surveys.
follow up on	to pursue or check the progress of	Please follow up on the pending invoices.
account for	to explain / to constitute a proportion of	Overheads account for nearly a third of the total cost.
write off	to cancel a debt as a loss / to dismiss as unimportant	The bank wrote off the unrecoverable loan.
phase out	to remove gradually	The company is phasing out its older product line.
bring forward	to move to an earlier date/time	They brought forward the shareholders' meeting by a week.
carry forward	to transfer to the next period	Unused leave can be carried forward to next year.
chip in	to contribute money or effort jointly	All the team members chipped in for the farewell gift.
touch base	to make brief contact to exchange updates	Let's touch base before the client call tomorrow.
iron out	to resolve minor difficulties	The two sides ironed out their differences before signing.
tide over	to help someone get through a difficult period	The emergency fund helped the firm tide over the crisis.

Travel and movement

Phrasal Verb	Meaning	Example Sentence
take off	to remove / (aircraft) to depart	The flight took off on schedule.
check in	to register at a hotel/airport	We checked in at the hotel around midnight.
check out	to leave a hotel after settling the bill	Guests must check out by noon.
set off	to begin a journey	They set off for the hills early in the morning.
get on	to board a vehicle	We got on the train just before it left.
get off	to leave/exit a vehicle	She got off the bus at the last stop.
pull over	to stop a vehicle at the side of the road	The driver pulled over to check the tyre.
set out	to start a journey or a plan	They set out at dawn to reach the summit by noon.
drop off	to leave someone or something at a place	He dropped off the parcel at the courier office.
pick up	to collect someone or something	She picked up her brother from the airport.
head for	to move towards a destination	The convoy headed for the border at first light.
break down (vehicle)	to stop working while travelling	Our car broke down halfway through the trip.

Communication and confrontation

Phrasal Verb	Meaning	Example Sentence
break out	to start suddenly (fire, disease, war)	A fire broke out in the warehouse.
get away with	to escape punishment	He won't get away with this mistake.
go ahead	to proceed	Go ahead with the plan; I approve.
turn down	to reject	The bank turned down his loan application.
back up	to support / to make a copy of data	Please back up all the files before the update.
back down	to withdraw from a position or demand	The union backed down after the talks succeeded.
break up	to end a relationship / to disperse	The crowd broke up once the rain started.
bring round	to persuade someone to agree	After a long talk, they brought him round to their view.
speak up	to talk more loudly or express an opinion openly	She spoke up against the unfair decision.
spell out	to explain in clear detail	The notice spells out the new attendance policy.
own up to	to admit responsibility	He finally owned up to the mistake.
talk someone out of	to persuade someone not to do something	Her friends talked her out of resigning impulsively.
stand up for	to defend	He stood up for his colleague during the inquiry.
back out of	to withdraw from a commitment	They backed out of the deal at the last moment.

Why this trips up exam-takers: phrasal verbs are near-impossible to guess from the individual words ("give up" has nothing literal to do with height), which is exactly why they appear so often in one-word-substitution and cloze-test questions — the examiner is testing memorized vocabulary rather than reasoning. The most efficient way to retain a list this size is the clustering shown above: learning "check in / check out / set off / get on / get off" together as a single travel-scenario story is far stickier than learning fifty unrelated definitions in alphabetical order.

3.7 Causative Verbs

Causative verbs — make, let, have, get — describe an action performed because one person causes, permits, or arranges for another person (or thing) to do it, rather than doing it personally.

• make + someone + base verb (to force/compel): The manager made the intern redo the entire spreadsheet.
• let + someone + base verb (to permit): Her father let her attend the workshop in Mumbai.
• have + someone + base verb (to arrange for someone to do something): We had the electrician check the wiring yesterday.
• get + someone + to + verb (to persuade/arrange, slightly less direct than "have"): She got her brother to fix the laptop.
• have/get + something + past participle (to arrange for something to be done to an object): He had his car repaired last week. / She got her passport renewed on time.

Exam trap — wrong form after causative verbs:

• Wrong: The teacher made the students to submit their assignments. Fix: The teacher made the students submit their assignments. ("make" is followed directly by the base form, never "to + verb")
• Wrong: She had her hair to cut yesterday. Fix: She had her hair cut yesterday. (the causative "have something done" pattern needs the past participle, not the infinitive)
• Wrong: He let his son to drive the car. Fix: He let his son drive the car. ("let" is followed directly by the base form, never "to + verb")
• Wrong: I got him fixing the printer. (ambiguous/incorrect for the intended meaning) Fix: I got him to fix the printer. ("get someone" is followed by "to + verb," not verb-ing, when the meaning is "persuaded/arranged for")
• Wrong: They had the report finish before the review. Fix: They had the report finished before the review. ("have something done" needs the past participle "finished," not the base form "finish")

3.8 Modal Verbs: Shades of Meaning

Modal auxiliaries change the meaning of a verb — ability, permission, possibility, obligation, or advice — without changing form for person or number. Exams test not just the grammatical rule (base form after a modal) but also the correct modal for the intended meaning, which is a subtler, more frequently missed skill.

can / could — ability and permission

• can expresses present ability or informal permission: She can operate this machine without help.
• could expresses past ability, or a more polite/tentative request: He could swim across the river when he was young. / Could you please forward this email?
• Exam trap: using "can" for a past-time context. Wrong: When she was a child, she can sing beautifully. Fix: When she was a child, she could sing beautifully.

may / might — possibility and formal permission

• may expresses a reasonably likely possibility or formal permission: You may leave the hall once you finish the exam.
• might expresses a weaker, more uncertain possibility, and is also the past/reported form of "may": It might rain later this evening.
• Exam trap: confusing degree of certainty. Wrong: He might be the manager here — I have seen his name on every approval. (context suggests near-certainty, so "may" or "must" fits better than the more tentative "might") Fix: He must be the manager here — I have seen his name on every approval.

must / have to — obligation and logical certainty

• must often expresses an obligation the speaker feels personally, or strong logical deduction: You must submit the form before 5 pm. / She hasn't eaten all day — she must be hungry.
• have to expresses an obligation imposed externally (by rules, other people, circumstances): Candidates have to carry their admit card to the exam hall.
• must not expresses prohibition, while don't have to expresses absence of obligation — these are frequently and deliberately confused in MCQs. Wrong (intended meaning: no obligation): You mustn't come if you're busy. Fix: You don't have to come if you're busy. ("mustn't" would wrongly imply it is forbidden, not merely optional)

should / ought to — advice and mild obligation

• Both express advice or a recommended action, and are close to interchangeable, though "ought to" is comparatively formal and less common in everyday speech. Wrong: You should to consult a doctor. Fix: You should consult a doctor. (no "to" after "should") Correct with "ought to": You ought to consult a doctor. ("ought" is the one modal that does take "to")

shall / will — future and formal offers

• In contemporary usage, "will" is standard for future tense across all persons in most exam contexts; "shall" survives mainly in formal offers/suggestions with "I/we" (Shall we begin the meeting?) and in some legal/regulatory drafting. Wrong: He shall attend the workshop next week. (in ordinary modern usage, this sounds oddly formal/legalistic for a simple future statement) Fix: He will attend the workshop next week.

need / dare — as modal or as ordinary verb

• As modals (mainly in negatives/questions), they don't take -s or "to": He need not worry about the results. As ordinary verbs, they behave regularly: He needs to submit the form. Exams sometimes test whether you can distinguish the two constructions in the same sentence. Wrong: He needs not attend the meeting. Fix (modal use, negative, no "to," no "-s"): He need not attend the meeting.

would — past habit, hypothetical, and polite request

• would has three distinct exam-relevant uses that are easy to conflate: a repeated past habit (We would visit our grandparents every summer), the main clause of a hypothetical conditional (If I had the funds, I would invest in that business), and a polite request or offer (Would you like some tea?). Confusing the hypothetical use with the past-habit use is Pattern 5 in Section 8.

3.9 Passive Voice and Verb Tense

The passive voice restructures a sentence so that the object of the action becomes the grammatical subject, using a form of "be" + past participle. Every one of the twelve tenses has its own passive form, and exam questions frequently test whether the correct "be" form and participle have been matched to the intended tense.

Tense	Active	Passive
Present simple	The staff updates the records daily.	The records are updated daily.
Present continuous	The team is preparing the report.	The report is being prepared.
Present perfect	She has completed the task.	The task has been completed.
Past simple	The clerk verified the documents.	The documents were verified.
Past continuous	They were painting the wall.	The wall was being painted.
Past perfect	He had submitted the form before noon.	The form had been submitted before noon.
Future simple	The board will announce the results.	The results will be announced.
Future perfect	They will have finished the audit by March.	The audit will have been completed by March.

Exam trap — wrong "be" form or missing participle in the passive: Wrong: The letter was wrote by him yesterday. Fix: The letter was written by him yesterday. (passive needs the past participle "written," not the past simple "wrote")

Wrong: The complaint is investigating by the committee. Fix: The complaint is being investigated by the committee. (present continuous passive needs "is being + participle," not "is + verb-ing")

Exam trap — intransitive verbs incorrectly forced into the passive (recall Section 3.1: verbs like happen, occur, arise, die, fall cannot take a passive form at all). Wrong: The accident was happened near the crossing. Fix: The accident happened near the crossing.

Exam trap — passive with modal verbs. Modal passives follow the pattern modal + be + past participle, and the "be" is frequently dropped or mismatched. Wrong: The proposal must approved before Monday. Fix: The proposal must be approved before Monday. Wrong: The work can finished by tomorrow. Fix: The work can be finished by tomorrow.

3.10 Confusable Verb Pairs

A short list of verb pairs that are frequently swapped in error-spotting questions because they look or sound related but follow different grammatical rules. (A larger, dedicated set of twenty-five confused irregular-verb pairs, with fuller worked examples, appears in Section 4.6.)

sit (intransitive) vs seat (transitive, to cause to sit) — sit–sat–sat vs seat–seated–seated. Wrong: The usher sat the guests in the front row. Fix: The usher seated the guests in the front row.

say vs tell — "say" does not take a personal object directly (needs "to"); "tell" requires a personal object. Wrong: He said me the truth. Fix: He told me the truth. / He said the truth to me.

do vs make — "do" generally refers to actions/tasks/duties in a general sense; "make" refers to creating or producing something. Wrong: She made her homework before dinner. Fix: She did her homework before dinner.

bring vs take — "bring" implies movement toward the speaker; "take" implies movement away from the speaker. Wrong: Please take this file to me when you come. Fix: Please bring this file to me when you come.

loose vs lose — "loose" is an adjective (not tight); "lose" is a verb meaning to misplace or fail to win. Wrong: Don't loose your temper during the interview. Fix: Don't lose your temper during the interview.

stationary vs stationery (not verbs, but frequently confused alongside verb-error questions) — included here because they often appear in the same "confusable words" clusters as verb pairs on exam answer keys: "stationary" means not moving; "stationery" means writing materials.

affect vs effect (as verb) — "affect" is a verb meaning to influence; "effect" is a verb (less common, meaning "to bring about") but far more commonly a noun. Wrong: The new policy will effect the entire department. Fix: The new policy will affect the entire department.

advise vs advice — "advise" is the verb; "advice" is the noun. This spelling-only distinction is a recurring trap in written-English sections. Wrong: She adviced him to consult a lawyer. Fix: She advised him to consult a lawyer.

3.11 Sequence of Tenses in Reported (Indirect) Speech

Reported speech — converting a direct quotation into an indirect statement — is one of the richest sources of combined tense-and-pronoun errors in exams, because it forces a test-taker to change several things simultaneously: the reporting verb, the tense inside the clause, pronouns, and time/place references.

The core rule: when the reporting verb ("said," "told," "asked") is in the past tense, the tense inside the reported clause generally shifts one step back:

Direct Speech Tense	Shifts To (Indirect)
Present simple	Past simple
Present continuous	Past continuous
Present perfect	Past perfect
Past simple	Past perfect
Present perfect continuous	Past perfect continuous
will	would
can	could
may	might
must	had to / must (unchanged, if still an obligation)

Original examples:

• Direct: She said, "I am writing a report." Indirect: She said that she was writing a report.
• Direct: He said, "I have finished my work." Indirect: He said that he had finished his work.
• Direct: They said, "We will attend the seminar." Indirect: They said that they would attend the seminar.
• Direct: She said, "I visited the museum yesterday." Indirect: She said that she had visited the museum the day before.
• Direct: He said, "I can solve this problem." Indirect: He said that he could solve that problem.

Time and place references also shift:

Direct	Indirect
now	then
today	that day
tomorrow	the next day / the following day
yesterday	the day before / the previous day
here	there
this	that
these	those
ago	before

Exception — universal truths and habitual facts stay in present tense even in reported speech: Wrong: The teacher said that the earth revolved around the sun. Fix: The teacher said that the earth revolves around the sun. (scientific/universal truths are not shifted back)

Exam trap — shifting pronoun but forgetting tense, or vice versa: Wrong: He said that I am tired. (should reflect the original speaker's own statement, correctly converted) Fix (if the original was "I am tired," spoken by "he"): He said that he was tired.

Wrong: She asked me where do I live. Fix: She asked me where I lived. (in reported questions, word order becomes statement order — no auxiliary inversion — and the tense shifts back)

Reported commands and requests use a to-infinitive after "told/asked/ordered," never the imperative form directly: Wrong: The officer ordered the recruits stand at attention. Fix: The officer ordered the recruits to stand at attention.

3.12 A Preview: Gerunds, Infinitives, and Conditionals

Two verb-form topics are large and important enough to deserve full, dedicated sections of their own rather than a brief subsection here: which verbs are followed by a gerund versus a to-infinitive (including verbs that change meaning depending on which one follows), and the complete set of conditional sentence types. Section 5 covers the first in full, with reference tables spanning more than sixty verbs; Section 6 covers the second, with all five conditional patterns and their characteristic exam errors. If your immediate concern is "remember doing" versus "remember to do," or "if I had known," jump directly to those sections — this subsection exists only to point you there rather than to duplicate that material.

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