Theoretical Grammar - Syntax

CENTRAL AND PERIPHERIAL ELEMENTS OF THE CAUSE.
peripheral element – not central, secondary.
Sentence may consist of several clauses. In order to discuss syntactic functions of clause elements, the elements, such as subject, verb, object, complement, adverbial – they are all functional elements. (it is not about form, it's about function). Subject is a functional element of a clause. There are central and peripheral elements of a clause. Not all clause elements are equally important. , some are even optional.
The most central element is ''V'' – the verb element ( the verb)., and then it is followed by object, and normally, precede by subject ( in English),forming the verb they can take one or two objects (Od, Oi) and /or a complement which follows the object.( SVOC)
In a verb element can be 5 units maximum.
The most peripheral element is an adverbial ''A'' that occurs:
either initially ( subject),
finally,( the clause constituent (in SVA structure) – as a verb),
medially.
peripheral el. are the most mobile elements.
The formula of clause constituents is:
(A)S (A) V(O)(O) (C) (A.....)
S and V – are obligatory, others are optional.
The formula apply to the central cases of declarative sentences. ( not any marginal cases or interrogative or subjunctives)
Why the verb element is considered the central element of a clause?
1.it is normally obligatory
2.it helps to determine what other elements must occur.
3.it's position is normally medial, ( not initial or final)
4.it can not normally be moved – it is immobile.
Adverbial characteristics.
1.their position is most frequently final,
2.they are optional,
3.they are mobile, (they can be shifted to the postposition peripherally)
4.they do not determine what other element occur.

Adverbial from a structural point (not stylistic) they may be regarded as optional extra. As optional extra which may be added as will.( we cannot add verbs or subj.)
English is regarded as a fixed word order language ( S V O is the core structure, SVO is the central order how the elements occur in a declarative sentence).
Latvian – is not fixed word order lang. English has not inflexions like Latvian .
In English the central core – SVO can not exchange the order)
e.g. Es vakar biju Londonā, Vakar es biju Londonā, Londonā es biju vakar.
e.g. She love him – him loves she, Loves him she – not possible.
e.g. John hit Mary, ( not Mary hit John) – the w.o itself specifies the meaning of the sentence.
Džons iesita Marijai. Marijai iesita Džons.

Consider the mobility of adverbial ''always''.
e.g. I always try and call her at weekend. I try and call her at weekend always, Always I try and call her at weekend .
There is no mobility of elements in central SVO structure. English has strict imitation of the ordering of a clause elements. The more peripheral an element is the more freedom of position it has.
The difference between of centrality can be observed not only in different elements of clause structure, but also between different subcategories of the same element.
Even if it is an adverb – there are difference between centrality and periphery.
Adverbial category – the most peripheral, but....within which there are relatively central and relatively peripheral types of the adverbial. Some are very central, some – peripheral.
''Always'' - adverbial
e.g. I always try and call her weekend. – always – mobile( position can be changed), optional.
There are adv. which cannot be moved – immobile.
There are adv, which are obligatory, such as the place adv.
e.g. You must put all the...upstairs.
Adv. are peripheral category, but there are cases which..
The place adverbial e.g. ..in the garden.., upstairs..- they as if complete the meaning of the verb, they are in a way a part of the verb.
Some grammarians classify the obligatory adv. as complements, there are theory that names that such obligatory adv. are complements.
adv. -obligatoriness, immobility – they resemble in their behaviour to be complements, but they are not complements.
There are elements which are called a sentence adverbials.- they tends to qualify by their meaning a whole sentence or clause, they do not refer to the specific unit, element.
e.g. To my regret, I received a square refusal.- separated by comma
e.g. She likes the garden, though.…