Infinitive Verbs

Exercises

Explanation

There are two main types of infinitives:

1. The “to-infinitive”

Form: to + verb

to write, to relax, to understand

2. The bare infinitive (without to)

Form: verb only

write, relax, understand

The bare infinitive appears after specific verbs and expressions.

1. The To-Infinitive

The to-infinitive is extremely common and can express:

• purpose or intention

• plans and goals

• reactions or feelings

• general actions

Examples:

I hope to join a photography course next month.
They agreed to help with the preparations.
She plans to study abroad after graduation.

Negative infinitive

Use not before the infinitive:

He promised not to forget again.
Please try not to make too much noise.

2. The Bare Infinitive (without “to”)

Some verbs and expressions require the infinitive without to.

A. After modal verbs

can, could, may, might, must, should, will, would

You must follow the instructions carefully.
We might go hiking tomorrow.

B. After verbs of perception

see, hear, feel, watch, notice

I saw the cat jump over the fence.
We heard the door close behind us.

(Exception: feel + to be uses to → “She felt it to be true.”)

C. After let, make, help

They let me use their Wi-Fi.
The music made everyone dance.
I helped her (to) carry the boxes. (both forms correct)

D. After certain expressions

had better, would rather, why not

You had better check the weather.
I'd rather stay inside tonight.
Why not try another solution?

3. Forms of the Infinitive

Infinitives are not tenses, but they can express different aspects or time relationships.

A. Simple Infinitive (Indefinite)

to + verb

Used for general actions or actions happening at the same time as the main verb.

She is delighted to meet you.
They were eager to begin the journey.

B. Continuous Infinitive

to be + verb-ing

Shows an action in progress.

He appears to be sleeping.
They seemed to be waiting for the bus.

C. Perfect Infinitive

to have + past participle

Shows an action completed before another action.

She is proud to have completed the marathon.
They seemed to have forgotten the plan.

Used after some past-tense verbs to show something expected but not done:

We hoped to have reached the village earlier.
He expected to have spoken to her already.

D. Perfect Continuous Infinitive

to have been + verb-ing

Emphasizes the duration of an action before another moment.

She seems to have been studying all afternoon.
He was happy to have been working with such a skilled team.

4. Passive Infinitive Forms

A. Simple Passive Infinitive

to be + past participle

The room needs to be cleaned.
He hopes to be invited to the conference.

B. Perfect Passive Infinitive

to have been + past participle

The documents seem to have been prepared.
I expected the package to have been delivered.

5. When We Use the Infinitive

A. After many common verbs

agree, decide, want, need, plan, expect, promise, offer, learn, attempt, fail, hope

They decided to open a new shop.
I expect to finish my work soon.

B. After question words

what, where, when, how, who, which

She can’t decide what to cook for dinner.
He showed us how to use the machine.

C. After would like / would love / would prefer

I would love to visit Japan one day.
We would prefer to leave early.

D. After adjectives

They were excited to start the project.
It’s difficult to explain this topic simply.

E. To express purpose (why someone does something)

She went to the shop to buy oranges.
He called me to ask a question.

F. In set expressions

to be honest, to tell the truth, to begin with, to sum up

To be honest, I wasn’t sure about the idea.
To sum up, we must improve our strategy.

6. Functions of the Infinitive

An infinitive can act as different parts of a sentence.

Subject: To exercise every day is good for your health.

Object: She wants to relax after work.

Part of a verb phrase: The work will have been completed by Friday.

Modifier (describes a noun):

I have a snack to prepare.
They bought a house to renovate.

Quick Summary

The infinitive = basic verb form

• to-infinitive: to learn, to read

• bare infinitive: learn, read

We use the infinitive to express:

• goals and intentions

• plans and expectations

• purpose

• feelings and reactions

• necessity or preference

It follows:

• many common verbs

• adjectives

• question words

• certain expressions and structures