Uses of Base Form (V1)
1️⃣ With Time Clauses
If the main clause is in the future, we use base form with time clauses starting with:
- when
- as soon as
- by the time
- after
- before
- as long as
- until
Examples:
When she arrives, we will start.
I will wait for him until he comes.
The students will have completed their assignments by the time the lecture ends.
Note: In above examples, we use present tense to talk about future time.
2️⃣ With Certain Verbs
Use base form with the following verbs:
- see
- watch
- hear
- notice
- observe
- feel
Examples:
You heard her sing a song.
I saw him eat the mangoes.
She felt the earth shake.
3️⃣ With Certain Expressions
Use base form after these expressions:
- couldn’t help but
- nothing but
- nothing except
- would rather than.
Examples:
He couldn’t help but laugh.
She did nothing but weep.
I would rather die than beg.
4️⃣ With Auxiliary Verbs
Use base form with the following auxiliary verbs : do, does, did.
Examples:
Does he come on time?
She did not participate in the debate.
Note: ‘Do, does, did’ are sometimes used in declarative sentences for emphasis.
Example: Ellen does understand the importance of honesty.
5️⃣ Use of Bid + Object + Base Form (V1)
After bid (meaning order or command), we use object + base form (V1) of the verb without “to.”
Example:
He bade me leave the room.
Uses of Past Form (V2)
1️⃣ Would rather + Person
Past form is used with ‘would rather + person’.
It is used for preference.
Examples:
I would rather Harry drove the car.
I would rather he helped me.
2️⃣ It is High Time
The past form is used with the expressions “It is time” and “It is high time.”
It is used for urgency.
Examples:
It is time we started the class.
It is high time he finished his work.
Uses of Past Participle (V3)
The Past Participle is used:
1️⃣ After the auxiliary verbs
- has
- have
- had
- will have
- shall have
Examples:
He has installed a new application.
She will have washed the clothes by evening.
2️⃣ In Passive Voice
The 3rd form of the verb is used to show that the action is done to the subject.
Structure:
Subject + be verb + V³
Examples:
- Tea was taken by me.
- The price of petrol has been increased.
✔ Here taken and increased are 3rd forms (past participles) used in passive voice.
3️⃣ As an Adjective
The 3rd form can also describe a noun, just like an adjective.
Examples:
- The police were searching the lost child.
- The broken glass injured her feet.
✔ Here lost and broken describe the child and glass, so they work like adjectives.
4️⃣ With Having
We use having + V3 to show that one action is completed before another past action.
Example:
Having finished her homework, she went to bed.
Uses of Gerund(V-ing)
1️⃣ After Certain Verbs
- enjoy
- finish
- suggest
- consider
- keep
- avoid
- miss
- deny
- admit
- mind
- postpone
- imagine
- spend
- recommend
Examples:
She finished washing the dishes.
He avoided meeting the stranger.
He suggested going for a walk.
Note: In these sentences the -ing form works as a noun
2️⃣ After Certain Expressions
We use gerund(V-ing) after the following expressions:
- get used to
- averse to
- look forward to
- devote to
- with a view to
- can’t help
- be used to
Examples:
He got used to smoking at an early age.
She went to the market with a view to buying a book.
Jane devoted her time to writing novels.
3️⃣ After Prepositions
We use gerund(V-ing) after prepositions.
Examples:
He succeeded in getting first position.
We insisted on staying indoors.
She is afraid of climbing the mountain. 
Common Mistakes
❌ He enjoyed to talk to his friend.
✅ He enjoyed talking to his friend.
❌ We will play as soon as he will return.
✅ We will play as soon as he returns.
❌ He was punished for come late.
✅ He was punished for coming late.
❌ I watched him to do his homework.
✅ I watched him do his homework.
❌ She was used to wake up early.
✅ She was used to waking up early.
❌ He would rather she marry him
✅ He would rather she married him.
❌ She is looking forward to see her grandmother.
✅ She is looking forward to seeing her grandmother.