Learning objectives
By the end of this lesson, you should be able to explain the main rules, identify the target forms in real sentences, avoid common errors and apply the rules to unfamiliar examples.
- Understand the core terms and distinctions.
- Study examples in context rather than memorising isolated rules.
- Complete the practice before opening the answer key.
1. What is a verb?
A verb expresses an action, event, process or state, and it is central to the predicate of a clause. A verb phrase may contain a main verb plus one or more helping (auxiliary) verbs.
Auxiliary + main verb: They are playing cricket.
Several auxiliaries: They might have been waiting.
2. Main verbs and auxiliaries
| Auxiliary | Common function | Example |
|---|---|---|
| be (am/is/are/was/were/been/being) | Progressive aspect; passive voice; linking verb when used alone | She is reading. / The door was opened. |
| have (have/has/had) | Perfect aspect | They have finished. |
| do (do/does/did) | Questions, negatives and emphasis in simple tenses | Do you agree? / I do understand. |
| Modal auxiliaries | Possibility, ability, advice, obligation and related meanings | You should rest. / It may rain. |
When be, have or do is the main verb, it may not be a helping verb: “I have a bicycle”; “She is happy”; “They did their homework.”
3. Action, linking, transitive and intransitive verbs
Action verbs express actions or events: run, write, arrive. Linking verbs connect the subject to a description or identity: be, seem, become, appear, remain and some uses of look, feel or taste.
“The chef tasted the soup.” — action verb + object.
A transitive verb takes an object in that use (“She opened the door”). An intransitive verb does not take a direct object (“The baby slept”). Some verbs can be both, depending on meaning: “The bell rang” / “She rang the bell.”
4. Verb forms
| Form | Example (write) | Use example |
|---|---|---|
| Base form | write | I write daily. |
| Third-person singular present | writes | She writes daily. |
| Past simple | wrote | She wrote yesterday. |
| Past participle | written | She has written a letter. |
| -ing form / present participle | writing | She is writing. |
Regular verbs usually form the past and past participle with -ed, but many common verbs are irregular: go/went/gone, see/saw/seen, take/took/taken. Learn irregular forms in context.
5. Finite and non-finite verbs; common errors
A finite verb is marked for tense and/or agreement in its clause: “She works here.” Non-finite forms include infinitives, -ing forms and participles: “to work,” “working,” “written.” These often depend on a finite verb or another structure.
- Incorrect: She do not like tea. Correct: She does not like tea.
- Incorrect: He has went home. Correct: He has gone home.
- Incorrect: Did you went? Correct: Did you go?
- Incorrect: They are know the answer. Correct: They know the answer.
After do/does/did, use the base form. After have/has/had in perfect constructions, use the past participle. After modal auxiliaries such as can, may, must, use the base form without to.
Guided practice
Try each item first. Then open the answer key and read the explanation for any answer you missed.
- Identify the auxiliary in “They have finished the work.”
- Choose: She ___ to school every day. (go / goes)
- Complete: Did he ___ the message? (send / sent)
- Choose the past participle: go / went / gone.
- In “The flowers smell sweet,” is smell linking or action?
- In “She smelled the flowers,” is smelled linking or action?
- Which sentence has an intransitive verb: “He slept” or “He kicked the ball”?
- Correct: “He has ate lunch.”
- Complete: You must ___ now. (leave / to leave)
- Is “to finish” finite or non-finite?
- Choose: They ___ watching TV when I arrived. (was / were)
- Which is the main verb in “The children are playing outside”?
- Choose: She does not ___ coffee. (drink / drinks)
- Which verb can be transitive or intransitive: ring? Give examples.
- Correct: “They are know the answer.”
Show answer key and explanations
- have — Have forms the present perfect with the past participle finished.
- goes — A third-person singular subject takes goes in the simple present.
- send — Did carries the past marking; the main verb uses its base form.
- gone — Gone is used with have/has/had in perfect constructions.
- Linking — Sweet describes the subject flowers.
- Action — The flowers are the direct object of smelled.
- He slept. — Slept has no direct object in this sentence.
- He has eaten lunch. — Perfect constructions require the past participle eaten.
- leave — A modal auxiliary is followed by the bare infinitive.
- Non-finite — The infinitive does not independently show tense or subject agreement.
- were — They takes were in the past progressive.
- playing — Are is the auxiliary; playing is the main verb.
- drink — After does not, use the base form.
- Both: The bell rang / She rang the bell. — The verb's use determines whether an object is present.
- They know the answer. — Know is normally a stative verb and is not usually used in the progressive in this meaning.
Revision checklist
- I can explain the main rule in my own words.
- I can identify the target form in a sentence.
- I can explain why a common incorrect example is wrong.
- I can apply the rule in a new sentence.
Do not judge mastery only by a score. If an answer was wrong, identify the rule behind the mistake and practise that pattern again.
Continue learning
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