Infinitive Mood of Verb:
(1) Generally ‘to‘ is placed before the verb to form the infinitive; as, to go, to sleep, to drink, to run, etc.
(2) But, ‘to‘ of the infinitive is omitted in the following cases-
(a) After the Verb bid, know, let, make, observe, please and also after the Verbs that denote some kind of perception; as, feel, hear, see, watch, behold, etc; as,
- I bade him go (i.e., to go).
- We have known him lead a careless life (i.e., to lead).
- Let him work (i.e., to work).
- Money makes the mare go (i.e., to go).
- I observed him raise his hat (i.e., to raise).
- He felt something touch his leg (i.e., to touch).
- I heard him sing (i.e., to sing).
- I saw or watched it fall (i.e., to fall).
- We beheld the train move (i.e., to move).
Note: To is not omitted when the above-mentioned Verbs except let are used in the Passive Voice; as, He was bidden to go. He was heard to sing. I was made to work till the evening.
(b) After the Verbs dare and need in the Negative and Interrogative sentences; as,
- He dare not do it.
- He need not go.
- How dare sing in my presence?
- Need you do it?
Note 1: If dare and need are preceded by an auxiliary verb to is not omitted.
- He did not dare to do.
- I did not need to sing.
Note 2: To is not omitted in the Affirmative or Positive sentences; as,
- He dares to do it.
- He needs to sing.
Note 3: In the Negative and Interrogative sentences a third person singular Subject does not require s with dare and need. But in the Affirmative sentences s is used with dare and need and to of the Infinitive is also used, as clear from the above example.
(c) After had better, had rather, would rather, had sooner, had as soon, rather than, etc; as,
- You had better take rest. (not, to take)
- I had rather go to bed. (not, to go)
- We would rather starve than beg. (not, to starve)
- You had sooner work than sleep. (you prefer working to sleeping)
- I would sooner go than stay. (I would prefer to staying)
- She had as soon walk as ride. (She should like equally well to walk or to ride)
(d) After but, except and than; as,
- She did nothing but weep. (not, to weep)
- We do everything except waste our time. (not, to waste)
- We are more likely to miss than catch the bus. (not, to catch)
(3) The Infinitive should not be split by inserting an Adverb or an Adverbial phrase between ‘to’ and principle Verb; as,
|I request you to kindly grant me leave.||I request you kindly to grant me leave.|
|You are required to immediately take up the work.||You are required to take up the work immediately.|
|I want you to thoroughly understand this point.||I want you to understand this point thoroughly.|
(4) The Infinitive has two important uses as (i) the simple or Noun Infinitive and (ii) the qualifying or Gerundial Infinitive. The simple or Noun Infinitive is used as Noun. The qualifying or Gerundial Infinitive is used to qualify a Verb, an Adjective, a Noun or a Phrase.
(a) The Noun Infinitive may be used as-
- Subject to a Verb; as, To err (Subject) is Human. To forgive (subject) is divine.
- Object to a Verb; as, We want to play (Object).
- Object to a Preposition (but, except, save, about); as, The bus is about to leave (Object to the preposition ‘about’).
- Complement to Verb; as, This shop is to let (Complement). I made him run (Complement).
- In apposition to Noun or Pronoun; as, It was his right to get his claim.
(b) The Gerundial Infinitive is used as-
- To qualify a Verb; as, We went to see the picture.
- To qualify an Adjective; as, The rose is to sweet to smell.
- To qualify a Noun; as, Here is a shop to let.
- To qualify a Sentence; as, To tell the truth, he is not honest. This medicine gives life to the dying, so to say.
(5) There are two forms of the infinitive: the Present Infinitive and the Perfect Infinitive; as,
Present Infinitive- to go, to sleep, to run.
Perfect Infinitive- to have gone, to have slept, to have run.
The Present Infinitive can be used with any tense of the finite verb.
The Perfect Infinitive is used-
(i) To express a wish, hope, intention or duty unfulfilled. It is generally used after the Verbs, ought, might, could, should and would. The action expressed by it does not actually occur; as,
- He might have come here. (But he did not come)
- You ought to have respected your teacher. (But you did not respect him).
(ii) After such words as appear, seem and expect to show that the action expressed by it happened before that expressed by the finite or governing Verb; as,
- She appears to have been healthy. (It appears that she was healthy once, but is not so now).
- She seems to be healthy. (She is healthy at the present moment).
(6) Some important Distinctions:
- I have to sell two books. (I have many books and out of these I want to sell two only).
- I have to two books to sell. (I have only two books which I want to sell).
- I shall have read it. (I shall have it read by somebody else).
- I expected you to have written a letter. (I expected you to write a letter and you did write).