Means of expressing modality in Modern English

1.2 Modal Words, Lexical Composition and Classification of Modal Words
A Modal word in a dictionary of linguistic terms (1969) as "the word has lost its specific lexical meaning and functioning as a means of descriptive expression of modality". Belyaeva M.A. English grammar gives the following definition: "modal words are words which express the subjective attitude of the speaker to the thoughts expressed in the sentence". Modal words are a part of speech to which the immutable words, expressing the subjective attitude of the speaker to the expressed thoughts. As to the form the modal words do not form a common external trait. However, two other feature-semantic and syntactic is presented clearly enough, that makes many linguists talk about modal words, as of a separate part of speech. Semantic feature of modal words is their subjective attitudes towards value creation from the point of view of their validity, the duration thereof or desirability. On the meaning modal words differ significantly from other major parts of speech with nominative function;
The syntactic function of modal words-function input member listings, or, much less often, word-suggestions. [4,40]
Modal words can function as the word-proposals, similar to the words of affirmation and negation Proposals-Yes and No. However, the words Yes and No-never change their status, whereas the modal words can be words, sentences (in dialogue) or be the introductory words in the sentence. Professor L.S. Barhudarov states that in the modal expression always play a role in induction of members. L.S. Barhudarov also gives the definition of modal words as words, have reported that the characteristics of the entire value in terms of its probability, capability, links with other facts, events, etc. In addition, Professor Barhudarov noted that not every word that serves as an introductory offer, the member belongs to the class of modal words. Modal words are special part of speech, and the induction of members may make and other parts of speech and word combination: adverbs, preposition, infinitive design, etc. These words are characterized by their immutability and combination with other words. [4,71]
Lexical Composition and Classification of Modal Words
In modern English the modal words include the following words:
Certainly, of course, no doubt, surely, apparently, assuredly, undoubtedly, indeed, evidently, naturally, obviously, really, actually, perhaps, maybe, probably, possibly, happily – unhappily, luckily – unluckily, fortunately– unfortunately.
The modal words can be subdivided according to their subjective by relation to the facts of reality into:
1) words expressing approval;
2) words that express assumption;
3) words expressing a subjective rating of the content of the remarks from the point of view of the desirability or otherwise of. [5,94]
Modal words have assumptions, doubt, likelihood, confidence speaking in the thought expressed in the sentence. Modal words serve as an introductory membership offer and generally refer to the proposal as a whole. Some modal words (for example, of course, certainly, no doubt, perhaps, etc.) can perform the function of Word-sentence» . Consider the following example:

• 
  Pickering: He taught you to speak. I couldn’t have done that.
  
• 
  Liza: Of course.
  
• 
  Пикеринг: Он научил вас говорить, я не мог это сделать.
  
• 
  Лиза: Конечно.
  

Modal words are words by which the speaker evaluates the expression as a whole or its separate parts from the point of view of their relationship to the objective reality. For example: it's true, the bone's eating sea ghoul; Circumstances, it is true you separated?
In these examples, the word, true, is a modal Word. It expresses the speaker's relationship to the content of the speech as perceived opportunities, in the first sentence the modal Word emphasizes the speaker's relationship to the content of the speech, and the second refers to one of the components of the speech to be. Having considered the data definition of modal words, we can say that the modal words occupy a special place in the system of parts of speech. Their total value is associated with the expression of a modality that is reported to the reality of the relationship that is established a talking person. Most modal words in the English language of adverbs and coincides with the image with the adverb suffix –ly, for modal words often are close to adverbs and particles, so the distinction between the first and last is sometimes difficult. [6,79]