The infinitive is a non-finite verb form typically formed by adding the word to before the base form of a verb, as seen in expressions like to play, to read, or to go.
Understanding how infinitives function in English grammar is essential for mastering sentence structure and syntax. For related rules, you can explore our detailed guide on verbs that are always followed by infinitive.
When Is the Sign of the Infinitive Omitted?
While the particle to is the primary sign of an infinitive, there are specific grammatical contexts where it is omitted.
After Active Voice Verbs
The sign of the infinitive is omitted after the active voice of the verbs please, see, let, make, know, feel, hear, bid, need, behold, watch, dare:
- Please (to) go there.
- I saw him (to) go home.
- Let him (to) come.
- He need not go there.
- He made me do it.
- We heard him say so.
- I watched him go.
- I have known him (to) go there.
[The use of to after bid is coming into vogue. Pocket Oxford has - Bid him go or to go.]
However, when these verbs (except let) are in the passive voice, to is not omitted:
- He was seen to come.
- I was made to sit down.
- Ram was heard to say so.
But, 'He was let go.'
After Auxiliaries and Defective Verbs
The infinitive sign is omitted after the auxiliaries and defective verbs can, do, has, have, may, must, shall, should, will, would:
- Can you (to) do this ?
- Do (to) go there.
- I will (am willing to) go.
After Specific Phrases with Had
It is omitted after the verb had in such phrases as had better, had rather, had sooner, had as soon .. as, etc.:
- I had better or had sooner (to) go.
- You had rather (to) remain here.
After Comparative and Exceptive Words
It is omitted after than, except, as, better, and also but when it is preceded by do:
- He is better able to walk than run (=than he is able to run).
- He did nothing but (to) laugh.
- He did everything except (to) carry out my order.
- He did not so much as (to) say he was sorry.
- Better (to) be with the dead.
What Are the Two Types of Infinitives?
Infinitives are broadly categorized into two types: the Simple or Noun Infinitive and the Gerundial (or Qualifying) Infinitive.
How Is the Simple or Noun-Infinitive Used?
The Simple or Noun-Infinitive functions similarly to a noun within a sentence:
- As the subject of a verb: To err is human.
- As the object of a verb: He likes to swim. I taught him to read. He was taught to read (retained object).
- As the complement of a verb: He seems to be rich. I saw him go. I ordered him to be punished.
- As the object of prepositions: Used with prepositions like about, but, except, and also than used as a preposition. Example: He is about to die. I cannot but (to) go there. He did nothing else than or except (to) laugh (Nesfield).
- Absolutely: Used in exclamation or interrogation. Example: To think that he would do so! And now what to do ?
How Is the Gerundial Infinitive Used?
The Gerundial Infinitive is used to express purpose, cause, condition or results, and may be attached:
- Adverbially to a verb: He came to see me. It came to pass. We eat to live.
- Adverbially to an adjective: I am sorry to hear this. He is ready to go. I am anxious to learn.
- Adjectivally to a noun: I have a house to let. Here is a chair to sit on.
- Absolutely or Parenthetically to a sentence: To tell the truth, I do not trust him. To be brief, I am ruined.
In colloquial English, when the verb has been already used, the verbal part of the infinitive is sometimes dropped, and to alone is used: "Will you go home ?' I like to (=to go home). Has he done the work ?" "He ought to (=to have done)."
What Is the Split Infinitive?
The Split Infinitive is the name given to an infinitive form in which the main verb is wrongly separated from to by some word between [কখনও কখনও Infinitive-এর to এবং Verb-এর মধ্যে অনা শব্দ বসাইয়া এ দুটিকে পৃথক (split up) করা হয়। এটা ঠিক নয়।] : I request you to kindly help me. I request you to quickly do this. The correct forms are-I request you to help me kindly. I request you to do this quickly.
[ But the use of the Split Infinitive has come to stay and occasionally serves a clear and useful purpose. Thus, in "Police schools have been started to better train rural constables," better cannot be shifted without injury to the sense or diction. ]
Key Takeaways
- An infinitive is typically formed using to before a verb.
- The sign to is omitted after certain active verbs, auxiliaries, and phrases like had better.
- Simple infinitives act like nouns, functioning as subjects, objects, or complements.
- Gerundial infinitives act adverbially or adjectivally to express purpose, cause, or result.
- Split infinitives separate the word to from the main verb, though modern usage sometimes accepts them for clarity.
Quick Practice
Test your understanding of infinitives by answering the questions below in the comments section:
- Identify whether the infinitive in "We eat to live" is a Simple Infinitive or a Gerundial Infinitive.
- Write a correct sentence avoiding a split infinitive based on: "I request you to kindly help me."
Frequently Asked Questions
What is an infinitive in English grammar?
An infinitive is the base form of a verb preceded by the word to (e.g., to run, to read), functioning as a noun, adjective, or adverb.
When do we omit the word 'to' in an infinitive?
The word to is omitted after modal auxiliary verbs (can, must, will), certain active verbs like let, make, and see, and phrases like had better.
What is a split infinitive?
A split infinitive occurs when an adverb or other word is placed between the particle to and the verb (e.g., to boldly go), which traditional grammar discourages.