Types of Infinitives in English (Page 2) (C-Level, Advanced)
Perfect Infinitives
Perfect infinitives (to have + past participle or have + past participle) express actions or states that occurred before the time referenced by the main verb. They are essential for establishing temporal relationships and often convey regret, speculation about the past, or criticism of past actions.
For example, in the sentence,
He claims to have finished the exam in 30 minutes
the main verb (claim) requires a to-infinitive; however, what is claimed (finishing the exam) is in the past; therefore, the construction requires a perfect infinitive, “to have earned,” which both is a to-infinitive and indicates a past action.
Uses of perfect infinitives
Perfect infinitives expressing past actions or unrealized possibilities
Examples
She claims to have seen the accident, but nobody else was there at the time.
The manager appears to have forgotten about our meeting yesterday.
He would have preferred to have been told about the changes before they were announced.
It was silly of me to have assumed that everyone would agree with my proposal.
Perfect infinitives with modal verbs (speculating about the past)
Examples
They must have known about the problem when they made the decision.
She may have misunderstood the instructions when she filled out the form.
The company should have informed customers about the data breach immediately.
The media might have exaggerated the story to make it more interesting.
Perfect infinitives expressing regret or criticism
Examples
It would have been better to have checked the weather forecast before planning the outdoor event.
The team ought to have noticed the mistake before sending the report to the client.
I would have liked to have joined you for dinner, but I wasn't invited.
Passive Infinitives
Passive infinitives shift focus from the agent to the action or recipient, following the pattern to be + past participle (simple passive) or to have been + past participle (perfect passive). These constructions are particularly prevalent in formal, academic, and professional registers.
Passive infinitive constructions
Examples
Simple passive infinitives (to be + past participle)
The essay needs to be rewritten before you can submit it to your teacher.
All employees expect to be treated fairly and with respect in the workplace.
The rule deserves to be changed because it's outdated and no longer makes sense.
She hopes to be promoted to manager next year after all her hard work.
Perfect passive infinitives (to have been + past participle)
Examples
The documents appear to have been lost during the office move last month.
He claims to have been misunderstood by his colleagues during the meeting.
The contract seems to have been signed without anyone reading all the details carefully.
I would have preferred to have been notified about the schedule change earlier.
Passive infinitives following modal verbs
Examples
These complaints must be taken seriously by the management team.
The results should have been shared with everyone before the final decision was made.
Your concerns cannot be ignored just because they're inconvenient to address.
Progressive Infinitives
Progressive infinitives (to be + present participle) emphasize ongoing action or temporary states. While less common than other infinitive forms, they are useful for expressing continuity or actions in progress at a specific reference point.
Progressive infinitive examples
She appears to be thinking about changing her mind, though she hasn't said anything yet.
The weather seems to be improving after several days of heavy rain.
At the time, we believed the project to be going well, but we didn't know about the problems.
He claims to be writing a detailed reply to the complaints, but he hasn't said when he'll finish it.
Up Next: Negative Infinitives
Continue the lesson to learn about negative infinitives, split infinitives, and infinitives in reported speech.