Infinitive Phrases and clauses Uses of the infinitive

Uses of the infinitive

The bare infinitive and the to-infinitive have a variety of uses in English. The two forms are mostly in complementary distribution – certain contexts call for one, and certain contexts for the other; they are not normally interchangeable, except in occasional instances like after the verb help, where either can be used.

The main uses of infinitives (or infinitive phrases) are as follows:

• 
  As complements of other verbs. The bare infinitive form is a complement of the dummy auxiliary do, most modal auxiliary verbs, verbs of perception like see, watch and hear (after a direct object), and the verbs of permission or causation make, bid, let, and have (also after a direct object). The to-infinitive is used after many transitive verbs like want, aim, like, fail, etc., and as an object complement of a direct object regarding verbs like want, convince, aim, etc.
  
• 
  In various particular expressions, like had better and would rather (with bare infinitive), in order to, as if to, am to/is to/are to.
  
• 
  As a noun phrase, expressing its action or state in an abstract, general way, forming the subject of a clause or a predicative expression: "To err is human"; "To know me is to love me". The bare infinitive can be used in such sentences like "What you should do is make a list." A common construction with the to-infinitive involves a dummy pronoun subject (it), with the infinitive phrase placed after the predicate: "It was nice to meet you."
  
• 
  Adverbially, to express purpose, intent or result, as the to-infinitive can have the meaning of in order to, e.g. "I closed the door in order to block out any noise."
  
• 
  As a modifier of a noun or adjective. This may relate to the meaning of the noun or adjective ("a request to see someone"; "keen to get on"), or it may form a type of non-finite relative clause, like in "the man to save us"; "the method to use"; "nice to listen to".
  
• 
  In elliptical questions (direct or indirect): "I don't know where to go." After why the bare infinitive is used: "Why reveal it?"
  

The infinitive is also the usual dictionary form or citation form of a verb. The form listed in dictionaries is the bare infinitive, although the to-infinitive is often used in referring to verbs or in defining other verbs: "The word 'amble' means 'to walk slowly'"; "How do we conjugate the verb to go?"

For further detail and examples of the uses of infinitives in English, see Bare infinitive and To-infinitive in the article on uses of English verb forms.

Other Germanic languages[edit]

The original Proto-Germanic ending of the infinitive was -an, with verbs derived from other words ending in -jan or -janan.

In German it is -en ("sagen"), with -eln or -ern endings on a few words based on -l or -r roots ("segeln", "ändern"). The use of zu with infinitives is similar to English to, but is less frequent than in English. German infinitives can form nouns, often expressing abstractions of the action, in which case they are of neuter gender: das Essen means the eating, but also the food.

In Dutch infinitives also end in -en (zeggen — to say), sometimes used with te similar to English to, e.g., "Het is niet moeilijk te begrijpen" → "It is not hard to understand." The few verbs with stems ending in -a have infinitives in -n (gaan — to go, slaan — to hit). Afrikaans has lost the distinction between the infinitive and present forms of verbs, with the exception of the verbs "wees" (to be), which admits the present form "is", and the verb "hê" (to have), whose present form is "het".

In North Germanic languages the final -n was lost from the infinitive as early as 500–540 AD, reducing the suffix to -a. Later it has been further reduced to -e in Danish and some Norwegian dialects (including the written majority language bokmål). In the majority of Eastern Norwegian dialects and a few bordering Western Swedish dialects the reduction to -e was only partial, leaving some infinitives in -a and others in -e (å laga vs. å kaste). In northern parts of Norway the infinitive suffix is completely lost (å lag’ vs. å kast’) or only the -a is kept (å laga vs. å kast’). The infinitives of these languages are inflected for passive voice through the addition of -s or -st to the active form. This suffix appearance in Old Norse was a contraction of mik (“me”, forming -mk) or sik (reflexive pronoun, forming -sk) and was originally expressing reflexive actions: (hann) kallar (“[he] calls”) + -sik (“himself”) > (hann) kallask (“[he] calls himself”). The suffixes -mk and -sk later merged to -s, which evolved to -st in the western dialects. The loss or reduction of -a in active voice in Norwegian did not occur in the passive forms (-ast, -as), except for some dialects that have -es. The other North Germanic languages have the same vowel in both forms.

Latin and Romance languages

The formation of the infinitive in the Romance languages reflects that in their ancestor, Latin, almost all verbs had an infinitive ending with -re (preceded by one of various thematic vowels). For example, in Italian infinitives end in -are, -ere, -rre (rare), or -ire (which is still identical to the Latin forms), and in -arsi, -ersi, -rsi, -irsi for the reflexive forms. In Spanish and Portuguese, infinitives end in -ar, -er, or -ir (Spanish also has reflexive forms in -arse, -erse, -irse), while similarly in French they typically end in -re, -er, oir, and -ir. In Romanian, both short and long-form infinitives exist; the so-called "long infinitives" end in -are, -ere, -ire and in modern speech are used exclusively as verbal nouns, while there are a few verbs that cannot be converted into the nominal long infinitive.^[3] The "short infinitives" used in verbal contexts (e.g., after an auxiliary verb) have the endings -a,-ea, -e, and -i (basically removing the ending in "-re"). In Romanian, the infinitive is usually replaced by a clause containing the conjunction să plus the subjunctive mood. The only verb that is modal in common modern Romanian is the verb a putea, to be able to. However, in popular speech the infinitive after a putea is also increasingly replaced by the subjunctive.

In all Romance languages, infinitives can also form nouns.

Latin infinitives challenged several of the generalizations about infinitives. They did inflect for voice (amare, "to love", amari, to be loved) and for tense (amare, "to love", amavisse, "to have loved"), and allowed for an overt expression of the subject (video Socratem currere, "I see Socrates running"). See Latin conjugation § Infinitives.

Romance languages inherited from Latin the possibility of an overt expression of the subject (as in Italian vedo Socrate correre). Moreover, the "inflected infinitive" (or "personal infinitive") found in Portuguese and Galician inflects for person and number. These, alongside Sardinian,^{[citation needed]} are the only Indo-European languages that allow infinitives to take person and number endings. This helps to make infinitive clauses very common in these languages; for example, the English finite clause in order that you/she/we have... would be translated to Portuguese like para teres/ela ter/termos... (Portuguese is a null-subject language). The Portuguese personal infinitive has no proper tenses, only aspects (imperfect and perfect), but tenses can be expressed using periphrastic structures. For instance, "even though you sing/have sung/are going to sing" could be translated to "apesar de cantares/teres cantado/ires cantar".

Other Romance languages (including Spanish, Romanian, Catalan, and some Italian dialects) allow uninflected infinitives to combine with overt nominative subjects. For example, Spanish al abrir yo los ojos ("when I opened my eyes") or sin yo saberlo ("without my knowing about it").^[4][5]
Hellenic languages[edit]