1. the subject of theoretical grammar its relations to other branches of linguistics

27. 28 A General Outline of the Verb as a Part of Speech The verb is the most complex part of speech. This is due to the central role it performs in realizing predication - connection between the situation given in the utterance and reality. That is why the verb is of primary informative significance in the utterance. Besides, the verb possesses a lot of grammatical categories. Furthermore, within the class of verbs various subclass divisions based on different principles of classification can be found.
Semantic features of the verb. The verb possesses the grammatical meaning of verbiality - the ability to denote a process developing in time. This meaning is inherent not only in the verbs denoting processes, but also in those denoting states, forms of existence, evaluations, etc.
Morphological features of the verb. The verb possesses the following grammatical categories: tense, aspect, voice, mood, person, number, finitude and temporal correlation. The common categories for finite and non-finite forms are voice, aspect, temporal correlation and finitude. The grammatical categories of the English verb find their expression in both synthetical and analytical forms.
Syntactic features. The most universal syntactic feature of verbs is their ability to be modified by adverbs. The second important syntactic criterion is the ability of the verb to perform the syntactic function of the predicate. However, this criterion is not absolute because only finite forms can perform this function while non-finite forms can be used in any function but predicate.
29 Classification of Verbs
Morphological classifications

1. 
   According to their stem-types all verbs fall into: simple (to play), sound- replacive (food - to feed, blood - to bleed), stress-replacive (‘insult - to in’sult, ‘record - to re’cord), expanded - built with the help of suffixes and prefixes (oversleep, undergo), composite - correspond to composite nouns (to blackmail), phrasal (to have a smoke, to take a look).
   
2. 
   According to the way of forming past tenses and Participle II verbs can be regular and irregular.
   

Lexical-morphological classification is based on the implicit grammatical meanings of the verb.
According to the implicit grammatical meaning of transitivity/intransitivity verbs fall into transitive and intransitive.
According to the implicit grammatical meaning of stativeness/non- stativeness verbs fall into stative and dynamic.
Dynamic verbs include:

1. 
   activity verbs: beg, call, drink;
   
2. 
   process verbs: grow, widen, narrow;
   
3. 
   verbs of bodily sensations: hurt, itch;
   
4. 
   transitional event verbs: die, fall;
   
5. 
   momentary: hit, kick, nod.
   

Stative verbs include:

1. 
   verbs of inert perception and cognition: adore, hate, love;
   
2. 
   relational verbs: consist, cost, have, owe.
   

According to the implicit grammatical meaning of terminativeness/non- terminativeness verbs fall into terminative and durative. This classification is closely connected with the categories of aspect and temporal correlation.
Syntactic classifications
According to the nature of predication (primary and secondary) all verbs fall into finite and non-finite.
Functional classification
According to their functional significance verbs can be notional (with the full lexical meaning), semi-notional (modal verbs, link-verbs), auxiliaries. Auxiliaries are used in the strict order: modal, perfective, progressive, passive.
30. The category of tense
Time is an unlimited duration in which things are considered as happening in the past, present or future. Time stands for a concept with which all mankind is familiar. Time is independent of language. Tense stands for a verb form used to express a time relation. Time is the same to all mankind while tenses vary in different languages. Time can be expressed in language in two basic ways: 1) lexically; 2) grammatically.
The category of tense is considered to be an immanent grammatical category which means that the finite verb form always expresses time distinctions. The category of tense finds different interpretations with different scholars.
According to one view, there are only two tenses in English: past and present. Most British scholars do not recognize the existence of future. It is considered to be a combination of the modal verb and an infinitive used to refer to future actions. The modal verbs “shall” and “will” preserve their lexical meaning of “wish, volition”. In that case combinations of the modal verbs with notional verbs should be regarded as free syntactical constructions, not as analytical structures. However, there are some examples in which the notion of volition cannot be implied:
eg. He will die in a week.
I shall be twenty next Friday.
Provided that the situation is realistic, in these contexts lexical meanings of “shall” and “will” are not present. These elements render only grammatical meanings, therefore they serve as auxiliaries and such combinations must be regarded as analytical structures. So we have to recognize the existence of pure futurity in English.
In traditional linguistics grammatical time is often represented as a three- form category consisting of the “linear” past, present and future forms. The meaning of the category of tense is the relation of the action expressed by a finite verb to the moment of speaking. Present denotes coincidence, past denotes a prior action, future denotes a posterior action which follows the moment of speaking.
The future-in-the-past does not find its place in the scheme based on the linear principle since it does not show any relation to the moment of speaking, hence this system is considered to be deficient, not covering all lingual data. Those who deny the existence of simple future in English consider future-in-the-past one of the mood forms. Those who recognize the existence of simple future argue that it is used in the same situation when simple future is used, in subordinate clauses when the principal clause contains a past form. So, this form is different only in one respect - it is dependent on the syntactic structure.
According to the concept worked out by Prof. Blokh, there exist two tense categories in English. The first one - the category of primary time - expresses a direct retrospective evaluation of the time of the process denoted. It is based upon the opposition of past vs. present, the past tense being its strong member. The second one - the category of “prospective time” - is based on the opposition of “after-action” and “non-after-action”, the marked member being the future tense.