Introduction actuality of the research paper

1.3General characteristics of Modal verbs
The group of modal verbs includes a small number of the verbs which are distinguished from all verbs with a number of characteristics in value, use and grammatical forms. These verbs have no actual verbal grammatical category (a look, a temporary denotation of pledge); they can have only the inclination and time forms which are indicators of a predicate. Owing to this fact, and also owing to absence of non-predicative forms (an infinitive, a gerund, participles), modal verbs stand on the periphery of verbal system in the English language.²¹
Verbs like can and may are called modal auxiliaries, though we often refer to them simply as modal verbs or modals. We frequently use modals when we are concerned with our relationship with someone else. We may, for example, ask for permission to do something; grant permission to someone; give or receive advice; make or respond to requests and offers, etc. We can express different levels of politeness both by the forms we choose and the way we say things.
Modals sharing the same grammatical characteristics are:
can could
may might
will would
shall should
must
ought to
Verbs which share some of the grammatical characteristics of modals are: need, dare, used to.
By comparison, need to and dare to are full verbs.
Modals have two major functions which can be defined as primary and secondary.
Primary function of modal verbs
In their primary function, modal verbs closely reflect the meanings often given first in most dictionaries, so that:
can/could relate mainly to ability: I can lift 25 kg./I can type.
may/might relate mainly to permission: You may leave early.
will/would relate mainly to prediction: It will rain soon.
shall after I/we relates mainly to prediction: Can we find our way home? Im sure we shall.
should/ought to relate mainly to escapable obligation or duty: You should do (or ought to do) as youre told.
must relates mainly to inescapable obligation: You must be quiet.
neednt relates to absence of obligation: You neednt wait.
Secondary function of modal verbs
In their secondary function, nine of the modal auxiliaries (not shall) can be used to express the degree of certainty/uncertainty a speaker feels about a possibility. They can be arranged on a scale from the greatest uncertainty (might) to the greatest certainty (must). The order of modals between might and must is not fixed absolutely. It varies according to situation. For example, one arrangement might be:
They designate opportunity, ability, probability, need of commission of the action expressed by a notional verb. As they express only modal relation, instead of action, they as a separate sentence part are never used. Modal verbs are always combined only with an infinitive, forming with it combinations which in the sentence is a complete modal predicate. Modal verbs are deficient verbs (Defective Verbs), because they do not have any forms that have other verbs. Lack of inflected-s in 3-person singular of the present tense is historically saying: modern forms of this time were the forms of the past tense, and 3 of the singular past tense was not personal.²²
Modal verbs must, should - ought, will-would, can-could, may-might, need can express various shades of the assumption. Scientists assume that modal verbs express objective reality, while parenthesises - subjective. It is possible to assume that verbs can and may specialize on transfer of possible, alleged actions, and verbs of must, should, might, besides value of obligation, transfer also alleged, probable actions, with value of parenthesises, such as perhaps, possibly, probably, certainly. When modal words and parenthesises are used at the same time, in such cases we deal with synonymous designs.

In the offer modal verbs are always combined with an infinitive (perfect and not perfect), forming with it one combination which is called a compound modal predicate. As separate sentence parts modal verbs are not used. The verb must is the assumption, usually based on knowledge and almost bordering on certainty. The combination of the verb must non perfect with infinitive means that the alleged action (or State) is simultaneous with the assumption and the assumption can refer both to the present and past time.
The verb must is used in the meaning of assumptions, the probability, that a great degree of confidence. A speaker believes it is plausible hypothesis. In this sense, the verb must roughly corresponds with the help of : evidently, apparently, certainly, most likely, probably.
The verbs customarily classed as modals in English have the following properties:

• 
  They do not inflect (in the modern language) except insofar as some of them come in present–past (present–preterite) pairs. They do not add the ending -(e)s in the third-person singular (the present-tense modals therefore follow the preterite-present paradigm).[a]
  
• 
  They are defective: they are not used as infinitives or participles (except occasionally in non-standard English; see § Double modals below), nor as imperatives, nor (in the standard way) as subjunctives.
  
• 
  They function as auxiliary verbs: they modify the modality of another verb, which they govern. This verb generally appears as a bare infinitive, although in some definitions, a modal verb can also govern the to-infinitive (as in the case of ought).
  
• 
  They have the syntactic properties associated with auxiliary verbs in English, principally that they can undergo subject–auxiliary inversion (in questions, for example) and can be negated by the appending of not after the verb.
  

1. 
   ^ However, they used to be conjugated by person and number, but with the preterite endings. Thus, they often have deviating second-person singular forms, which still may be heard in quotes from the Bible (as in thou shalt not steal) or in poetry.²³
   

The following verbs have all of the above properties, and can be classed as the principal modal verbs of English. They are listed here in present–preterite pairs where applicable:²⁴

• 
  can and could
  
• 
  may and might
  
• 
  shall and should
  
• 
  will and would
  
• 
  must (no preterite; see etymology below)
  

Note that the preterite forms are not necessarily used to refer to past time, and in some cases, they are near-synonyms to the present forms. Note that most of these so-called preterite forms are most often used in the subjunctive mood in the present tense. The auxiliary verbs may and let are also used often in the subjunctive mood. Famous examples of these are "May The Force be with you." and "Let God bless you with good." These are both sentences that express some uncertainty; hence they are subjunctive sentences.
The verbs listed below mostly share the above features but with certain differences. They are sometimes, but not always, categorized as modal verbs.[3] They may also be called "semi-modals".

• 
  The verb ought differs from the principal modals only in that it governs a to-infinitive rather than a bare infinitive (compare he should go with he ought to go).
  
• 
  The verbs dare and need can be used as modals, often in the negative (Dare he fight?; You dare not do that.; You need not go.), although they are more commonly found in constructions where they appear as ordinary inflected verbs (He dares to fight; You don't need to go). There is also a dialect verb, nearly obsolete but sometimes heard in Appalachia and the Deep South of the United States: darest, which means "dare not", as in "You darest do that."
  
• 
  The verb had in the expression had better behaves like a modal verb, hence had better (considered as a compound verb) is sometimes classed as a modal or semi-modal.
  
• 
  The verb used in the expression used to (do something) can behave as a modal, but is more often used with do-support than with auxiliary-verb syntax: Did she used to do it? (or Did she use to do it?) and She didn't used to do it (or She didn't use to do it)[a] are more common than Used she to do it? and She used not (usedn't) to do it.
  

Other English auxiliaries appear in a variety of different forms and are not regarded as modal verbs. These are:

• 
  be, used as an auxiliary in passive voice and continuous aspect constructions; it follows auxiliary-verb syntax even when used as a copula, and in auxiliary-like formations such as be going to, is to and be about to;
  
• 
  have, used as an auxiliary in perfect aspect constructions, including the idiom have got (to); it is also used in have to, which has modal meaning, but here (as when denoting possession) have only rarely follows auxiliary-verb syntax (see also § Must and have to below);
  
• 
  do; see do-support.
  

For more general information about English verb inflection and auxiliary usage, see English verbs and English clause syntax. For details of the uses of the particular modals, see § Usage of specific verbs below
he modals can and could are from Old English can(n) and cuþ, which were respectively present and preterite forms of the verb cunnan ("to be able"). The silent l in the spelling of could results from analogy with would and should.²⁵
Similarly, may and might are from Old English mæg and meahte, respectively present and preterite forms of magan ("may, to be able"); shall and should are from sceal and sceolde, respectively present and preterite forms of sculan ("to owe, be obliged"); and will and would are from wille and wolde, respectively present and preterite forms of willan ("to wish, want").²⁶
The aforementioned Old English verbs cunnan, magan, sculan, and willan followed the preterite-present paradigm (or, in the case of willan, a similar but irregular paradigm), which explains the absence of the ending -s in the third person on the present forms can, may, shall, and will. (The original Old English forms given above were first and third person singular forms; their descendant forms became generalized to all persons and numbers.)
The verb must comes from Old English moste, part of the verb motan ("to be able to, be obliged to"). This was another preterite-present verb, of which moste was in fact the preterite (the present form mot gave rise to mote, which was used as a modal verb in Early Modern English; but must has now lost its past connotations and has replaced mote). Similarly, ought was originally a past form—it derives from ahte, preterite of agan ("to own"), another Old English preterite-present verb, whose present tense form ah has also given the modern (regular) verb owe (and ought was formerly used as a past tense of owe).
The verb dare also originates from a preterite-present verb, durran ("to dare"), specifically its present tense dear(r), although in its non-modal uses in Modern English it is conjugated regularly. However, need comes from the regular Old English verb neodian (meaning "to be necessary")—the alternative third person form need (in place of needs), which has become the norm in modal uses, became common in the 16th century
A modal verb serves as an auxiliary to another verb, which appears in the infinitive form (the bare infinitive, or the to-infinitive in the cases of ought and used as discussed above). Examples: You must escape; This may be difficult.
The verb governed by the modal may be another auxiliary (necessarily one that can appear in infinitive form—this includes be and have, but not another modal, except in the non-standard cases described below under § Double modals). Hence a modal may introduce a chain (technically catena) of verb forms, in which the other auxiliaries express properties such as aspect and voice, as in He must have been given a new job.
Modals can appear in tag questions and other elliptical sentences without the governed verb being expressed: ...can he?; I mustn't.; Would they?
Like other auxiliaries, modal verbs are negated by the addition of the word not after them. (The modification of meaning may not always correspond to simple negation, as in the case of must not.) The modal word can combine with not forms the single word cannot. Most of the modals have contracted negated forms in n't which are commonly used in informal English: can't, mustn't, won't (from will), etc. Again like other auxiliaries, modal verbs undergo inversion with their subject, in forming questions and in the other cases described in the article on subject–auxiliary inversion: Could you do this?; On no account may you enter. When there is negation, the contraction with n't may undergo inversion as an auxiliary in its own right: Why can't I come in? (or: Why can I not come in?).