Descriptive Grammar: a shortcut

Descriptive Grammar: a shortcut

Traditional language components: 3 major components: phonology, grammar and lexicon.
Phonology – describes the sound system (consonants, vowels, stress, intonation)

Grammar – a set of structural rules governing the composition of clauses, phrases, and words. 2 basic units of grammar – word and sentence.

Lexicon – lists words and phrases, specifying how they are pronounced and what they mean.
New component – Pragmalinguistics – deals with the aim of the speaker (plain information, intention, requests, invitation) and the acts performed by what is being said.

Morphology (deals with the form of word) is focused on the internal structure of words. Word-formation morphology studies rules of the creation of new words. Inflectional morphology studies grammatical forms of words.
Syntax studies the internal structure of sentences and the relations between their component. They examine the rules that govern the way we build sentences and determine their relative grammaticality.
Descriptive vs. prescriptive grammar. Descriptive grammar - clear grammar that describes the grammatical constructions of a language, ot also refers to the structure of a language as it is actually used by speakers and writers. Prescriptive grammar (what is grammatically correct) refers to the structure of a language as it should be used.
Standard English is the variety of English that is “correct” because it shows none of the regional or other variations that are considered to be ungrammatical. Received Pronunciation (RP), is the way in which Standard English is spoken without regional variations. Is used in the media and by public figures, so it has a prestigious status.
Differences between formal and informal styles:

formal language no contractions, such as they’re, can’t, isn’t;
fewer phrasal verbs;
more past tenses (remote forms) of modal auxiliaries;
more passive voice, making communication less personal;
formal language uses more vocabulary derived from French and Latin

Structuralism, generative-transformational grammar. Modern descriptive linguistics is more of a structural approach to, that a language is a system. In 20th century linguistics developed a generative-transformational grammar. The goal of which is to make a complete model of this inner language that could be used to describe all languages and to predict the grammaticality of any given utterance.
Chomsky’s generative–transformational model analyses sentences into a series of related levels based on by rules. The key features of this model:

(1) Phrase-structure rules generate an underlying or deep structure which is

(2) transformed by transformational rules relating one underlying structure to another (e.g. active to passive), to produce

(3) a final surface structure, which itself is subject to phonological and morphemic rules.

The structure relations described in this model are held by Chomsky to be a universal feature of any language. The basic of such structures are kernel sentences, which are simple, active, declarative sentences that require the minimum of transformation.

Parts of speech. Word classes based on three types of criteria: notional (meanings), morphological (forms), and grammatical (relations with other words and larger units)” Some linguists say eight parts of speech: verb, noun, adjective, adverb, preposition, determinative, coordinator, subordinator
parts of speech divided into two: content words (open classes): nouns, verbs (except auxiliaries), adjectives, adverbs;
function words (closed classes): determinatives, prepositions, coordinators, subordinators, pronouns.
Content words Content words have meaning on their own: dog, sleep, pretty, slowly. They have the primary meaning of an utterance, and are variable in form (inflected). They are open classes (because readily accommodate the addition of new members as the vocabulary of the language develops and broadens), while old content words become archaic.
Function words create grammatical relationships into which the content words may fit. Function words give grammatical information about other words, and cannot be isolated from them. E.g. the, to, at, that, etc. have no meaning on their own, much fewer in number in comparison to content words, and they are invariable in form (except demonstratives, modals and some pronouns). Category is called closed because new words are not added to this group.
Verb and verb ph. serve important functions in a sentence. 1) are predicates, e.g. My father disappeared. Verbs and verb ph. can be 2)noun phrase modifiers (The man reading the book just looked at me), or 3)adjective phrase complements (The students seemed eager to learn grammar). 4)In the form of present participles and infinitives they can also serve as subjects of sentences (Running made me very tired;) or 5)subject complements (His favourite pastime is going to the cinema;).

Modal verbs. Express two main types of meaning:

1. human control over events, permission, intention, ability or obligation (subjective modality):

- You may leave now. (permission)

- I could speak Greek when I was young. (ability)

- You must go to bed at once. (obligation)

2. judgment whether an event was, is or will be likely to happen (objective modality): They may be away for the weekend. (‘It is possible that they…)

Verbs expressing necessity. Must has the most general meaning. To have to do - duty, obligation, reluctance. To need to - are interested in doing. Should (ought to) do - moral obligation (it is a good thing to do or the right thing to do). To be to is neutral and refers to something planned.
Noun a word which is used to denote a person, a concrete or abstract entity, e.g. fork, truth, a place, e.g. office, bus station. These are common nouns. Proper nouns (with a capital letter) - the names of specific people, places, events, e.g. New York, John, Christmas, Saturday. In a sentence a noun can be as a subject, an indirect object, a direct object, an appositive, a subject complement, an object complement, or as a modifier.
Countable and uncountable nouns. Countable nouns therefore have both a singular and a plural form and they can be accompanied by determiners that refer to distinctions in number: a (one, every) student Uncountable something that is viewed as and indivisible mass, that could not be counted. E.g. information, furniture. Uncountable nouns are singular and can be accompanied by determiners that have no distinction in number: much (your, that) information. Numbers are not used with uncountable. 1) You cannot use singular countable nouns alone (without a/the/my etc.). 2) You can use some and any with uncountable and plural countable nouns. 3) We use many and few with plural countable nouns: We use much and little with uncountable nouns:
An adjective - word describes or modifies or delimits another element referring to a thing in the sentence. It can be in such positions in a phrase:

attributive, i.e. before the noun as in clear water;
predicative, i.e. following any form of the verb be (e.g. am, is, was, been) and similar verbs (seem, appear, become) as in the water became clear, the beaches are beautiful;
postpositive, e.g. something interesting;

Adverb. Adverbs qualify the the verb in the clause, but they can be used to add more info to an adjective or other adverb, e.g. awfully good, slowly. Adverbs are made from adjectives adding the ending –ly, e.g. quickly, but adverbs can also have other forms, e.g. just, soon, rather, almost, too, etc.
Interjections, also called “filled pauses”, words show excitement or emotional involvement and are not grammatically connected to the rest of the utterance. Typically placed at the beginning of a sentence followed by punctuation marks: comma or exclamation mark. Could be expressed as single words (e.g.oh, oops) or non-sentence phrases (e.g. Oh god!) Belong to open class category but are function words.
Closed classes: Prepositions The relation of two parts of a sentence. Include words: in, on, under, beside, before, opposite. Often relations are to do with time or space, but other types of relations (possession, method, cause and effect) are expressed by using prepositions. Are short, but some prepositions are multi-word units; for example out of, by means of, up to, etc. Unless they are part of a verb (get in, pick up), prepositions are followed by a phrase containing a noun – at school, over the moon.
Determinatives, determine noun phrases. > articles the, a, an, possessive pronouns (my, his), > demonstratives (this, that, these, those), >quantifiers (any, some, many), > relative pronouns (which). We cannot put two determinatives in the same noun phrase. There are determinatives which can come before the central determinatives, (both your parents, all the books) or follow them, e.g. every (his few mistakes, the many questions).
Conjunctions connect clauses, phrases or words together to make longer constructions. 2 types: the coordinating conjunction (coordinator) and the subordinating conjunction (subordinator). Coordinators - connect elements that have the same grammatical status, e.g. main clause to main clause, phrase to phrase, noun to noun. Coordinating conjunctions: and, but, for, nor, or, so, and yet. Subordinator connect unequal clauses. Main clause is connected to a subordinate clause with the help of a these conjunction: after, although, as, because, before, if, since, that, until.
A pronoun word used instead of noun or group of nouns. Personal (I, me, you, him, them, etc.), demonstrative (this, that, these, those), possessive (mine, yours, his, hers, etc.), interrogative (what, who, which, whom, whose), reflexive (myself, himself, themselves, etc.), reciprocal (each other, one another), indefinite (another, much, nobody, few, etc.), relative (who, whom, which, that, whoever, whomever, whichever).
Morphology concerned with internal construction of words a: inflectional morphology and word-formation. Inflectional morphology studies process of adding units (inflectional morphemes) to a word, indicate grammatical information, (number in noun; mood, tense, person, or aspect in verbs; grade in adjectives and adverbs). In English inflection is done by affixation (e.g. shoes, walks, walking), sometimes via vowel change (ride - rode). Word-formation studies creation of new words with the help of derivational morphemes, or by simply changing grammatical category (for example, changing a noun to a verb).
Inflectional Morphology. Lexeme an abstract unit of morphological analysis:

represents a particular part of speech (functional criterion);
has a certain meaning (semantic value);
has different grammatical forms (formal criterion).

A lexeme is a unit regardless of any inflectional endings it may have or the number of words it may contain

Types of morphemes. Morpheme - minimal unit of language impossible to divide into smaller meaningful/grammatical elements. Morphological structure: Complex words are made of two or more morphemes, simple words contain one morpheme. Complex word consist of (1) a base (or root) and affixes (e.g. slower)(2) more than one root if they are compounds (blackmail). 2 types of morphemes: free morphemes, such as dog, read, dry, are meaningful individual elements, belong to a particular part of speech, can be alone in a sentence. Bound morphemes - meaningful units. Do not belong to any lexical category and must be attached to bases (stems or roots).
Bound morphemes. The attachment of bound morphemes modifies grammatical or lexical category of free morphemes. 2 types of bound morphemes: Inflectional morph modify the grammatical class of words by signalling a change in number, person, gender, tense, grade. Never change the syntactic category of the word. Derivational morph. modify a word’s lexical and grammatical class, results in deriving (constructing) a new word. Inflectional morphemes usually follow derivational ones.
Base forms: stems and roots. Morpheme, from which other grammatical forms or other words can grow, usually by adding affixes, is called a base. Base element of word structure with no inflections - stem. They are morphologically complexe.g. girlfriend, words with derivational morphemes, e.g. deepen. Derivational affixes are part of the stem. Root is the base form of a word which cannot be analysed into smaller parts.
Word-formation describes the process how new words are created, and studies the form of existing complex words (those composed of more than one morpheme). The of frequency of use and the number of examples, word-formation processes are: major word-formation processes: compounding, affixation and conversion, and minor word-formation processes: abbreviation, blending, clipping, coinage, and back-formation. Word-formation processes: productive, less productive or unproductive
Compounding the process where different words are joined together to form a single word. Compounding - productive word-formation process in English. Any two words can be combined to form a compound. There is no limit on how many words could be used. Some English compounds: windmill, snowflake, fingerprint, absent-mindedness, salt and pepper, once-in-a-lifetime. Sometimes meaning of compound cannot be predicted from the separate meanings of the words from which it is composed.
Affixation process creating new lexemes from lexemes adding derivational affixes, which are bound. When bound derivational morphemes (prefixes and suffixes), added to free ones, they change meaning of the base. Prefix is a bound morpheme position is preceding a root, a-, be-, de-, dis-, in-, infra-, mis-, pre-, re-, un-. Suffix is following a root, -able, -ate, -er, -ful, -hood, -ify, -ise, -ion, -less, -ness, -or, -tion, etc. Derivational affixes: either class-changing (suffixes) or class-preserving (most prefixes) morphemes.
Conversion, or zero derivation type of derivation - no morphemes are added – conversion is a change in lexical category of a word without changing form. Modification could be in word stress: convert, conduct, transport used as nouns (first syllable stressed), verbs (second syllable stressed). Conversion in Eng fairly productive process. The most productive forms of conversion in Eng - noun to verb conversion - verbification and verb to noun conversion - nominalisation.
Abbreviation - word formation, when the first letters (or parts: ampere meter - ammeter) of phrase put together to form a word. Is initialism or an acronym. Difference - how the words are pronounced, namely whether letter by letter, without intermission. Initialisms pronounced as sequences of letters,VIP (Very Important Person), TV (Television), DJ (Disc Jockey). Acronyms pronounced as ordinary words, with the same meaning as the original phrase, e.g. AIDS (Acquired Immune Deficiency Syndrome), NATO (The North Atlantic Treaty Organisation), radar (Radio Detection and Ranging), dinky (double income, no kids yet)
Blending formation of word from two bases with reduction of one or both at the boundary between, brunch (from breakfast + lunch), motel (from motor + hotel), newscast (from news + broadcast), workaholic (from work + alcoholic), smog (from smoke + fog). Parts of words are reduced in the blend, nonetheless the initial components are still recognizable. Blending is like compounding, but it is characterized by taking only parts of words and joining them.
Clipping - shortening long words by reducing a part of the original word to leave a shorter sequence. Common in Eng: information to info, advertisement to ad, refrigerator to fridge, telephone to phone. People’s names can be clipped to nicknames, Jen = Jennifer, Liz = Elizabeth.
Coinage creation of new words “from scratch”, without using other words via other word formation processes. Process not frequent, still companies try to compete and invent new names for products aspirin, nylon, xerox.
Backformation forming a new morphologically simpler word from a complex one. Process- a word (usually a noun), changes form and function − becomes reduced and used as a verb, arms meaning “weapon” was backformed to arm to mean “provide weapons”, similarly edit was backformed from editor, baby-sit from baby-sitter, headhunt from headhunter, typewrite from typewriter, and televise from television.
SYNTAX. Constituent Structure. Sentences constructed from smaller parts such as words, phrases, clauses. Constituent structure - hierarchical composition of bigger wholes from smaller parts called constituents.

Constituent structure analysis is based on the following principles:

sentences have parts, called constituents, may themselves have parts;
the parts of sentences belong to a limited range of types;
parts have specific functions within larger parts to which they belong.

Minor syntax Phrase structure rules represent internal structure of sentences. Basic operations join syntactic units together:

Det + N = noun phrase (NP): the + book = the book

Aux + V + NP = verb phrase (VP): will + write + the book = will write the book

NP + VP = clause (Cl): John + will write the book = John will write the book

Phrases combine to form clauses. Clause composed of noun phrase and verb phrase, and noun phrases and verb phrases can have internal structures, even containing other noun phrases or verb phrases. Clause is a constituent containing smaller constituents: [Cl[NP] [V[NP]]]: [[John] [will write [the book]]]

Tree diagrams are most often drawn above the item being diagrammed. A tree consists of nodes. Node has a label, e.g. NP for noun phrase, VP for verb phrase. Node at the top of the tree, the one from which all the others derive, is the root of the tree. Nodes connected by lines - edges.

Trees are upside down, with the root at the top, branches at the bottom. Parts of the analysed clause at the first level down, NP the boy and the VP stole the sweets are called immediate constituents of the clause, and stole and the sweets - immediate constituents of VP stole the sweets. Separate words - the smallest constituents, called ultimate constituents.

Constituency tests helps to determine constituents. To test whether a string of words is a constituent , we have‘modal’ adverb insertion test. ‘Modal’ adverbs used to express the speaker’s view of possibility in clause or sentence. Can be placed anywhere in the sentence, unless do not interrupt a constituent.

*The evidently boy stole the sweets

*The boy stole evidently the sweets.

*The boy stole the evidently sweets.

Last three are incorrect, because involve interruptions in constituent structure of the analysed sentence.

The coordination test stands for grammatical connection of elements: words, phrases or clauses (called conjuncts), similar in importance and structure. Relies on the fact that only constituents of same syntactic category can be joined by conjunctions such as and, but, or, nor, for, yet, so. Constituents that cannot be coordinated with other constituents of same syntactic category are not constituents.
Stand-alone (question test) refers to ability of constituents to be alone as answers to questions. Used to test constituency of a VP, but can be used in other phrases. What did you do yesterday? Went to a disco - *Went to
Substitution test involves using the so-called pro-forms in place of phrase or clause. Pro-forms - words that depend on an antecedent elsewhere in sentence or discourse for their meaning. Examples pro-forms pronouns: she, he, it; pro-VPs: do so, did it; pro-PPs: there, here. If group of words can be substituted by pro-form and change yields a grammatical sentence where general structure hasn’t been distorted, then sequence of words which is substituted with a pro-form is a constituent (underlined)

I know the boy who stole the sweets. - I know him.

The preposing test. Only constituents may be moved as single unit to the front of a sentence. We met in the street. - In the street, we met.
The cleft test Clefts used if speaker wants to emphasize particular constituent. Cleft sentences can be constructed: it + inflected form of be + X + subordinate clause, It was X that Y. - where X is the highlighted constituent. Consider: Tom’s girlfriend bought a sports car - It was Tom’s girlfriend who bought a sports car - It was a sports car that Tom’s girlfriend bought – not * It was Tom’s that bought girlfriend a sports car or * It was Tom’s girlfriend bought that a sports car
A phrase is group of words that functions as single unit in the structure of sentence. Not separate words but phrases (basic syntactic elements called constituents), build up clauses. Clause is the smallest unit - expresses a complete proposition in form of organised structure composed of phrases. An Eng clause contains subject and predicate. Phrase consists of head and its dependents. Head is important word - defines type of phrase. Lexical category of head gives its name to the phrase category, phrase a handsome teacher is a noun phrase - its head word teacher is a noun. Phrase ate an apple - verb phrase because its head is the verb ate.
Types of phrases. On the basis of the type of head:

noun phrase (NP) noun = head, a tall guy with blue eyes

verb phrase (VP) verb = head, can swim well, brought a bottle of wine

adjective phrase (AdjP) adjective = head extremely clever

adverb phrase (AdvP) adverb = head very slowly, almost never

preposition phrase (PP) preposition = head, in love, over the bridge

determinative phrase (DP) determinative = head rather few, quite many

Head is distinguished from its dependents, that is the rest of phrase other than the head. In NP a small bar on the outskirts of the city, we can find following dependents of the head bar: a, small, and on the outskirts of the city, long prepositional phrase including shorter prepositional phrase of the city, itself includes a smaller phrase the city.
Pre-modification. Determiners, nominal and adjective modifiers occur before NP head. Based on pre-head dependents, NP can have structures:

noun: I, Tom, people, friends

determiner + noun: the boy, a book, our house, those people, many people

determiner + adjective (modifier) + noun: a new house, my best friend

determiner + noun (modifier) + noun: a university teacher, wedding dress

quantifier + determiner + noun: both my children, all those people

quantifier + determiner + adjective (modifier) + noun: both my beautiful children, all those tired people

Determiners Role of determiner is implication of the definiteness of NP. Various types of determinatives (the examples are in bold) serve syntactic function of a determiner:

indefinite or definite articles, e.g. a little girl, the little girls

possessives, e.g. my little girls, Jane’s little girl

demonstratives, e.g. this little girl, those little girls

quantifiers, e.g. every little girl, some little girl, no little girl

numerals, e.g. one little girl, thirty little girls

relative determiners, e.g. which little girl, whose little girls

Post-modification. Basic types post-modifiers (in bold):

prepositional phrases, a baby with blue eyes, her knowledge of grammar

finite clauses, e.g. the girl who lives next door, the day I met my husband

non-finite clauses, e.g. the girl working for us, novels written by Eco

to-infinitive clauses, e.g. the events to happen

verbless clauses, the contestants, some of them primary schoolchildren,

adjective phrases, something different, everyone present at the meeting

adverb phrases, e.g. the road back, the old man here

noun phrases, e.g. clothes this size, the film “Shrek”

reflexive pronouns, e.g. Tom himself, my parents themselves

appositive noun phrases my wife Betty, Tusk, the Prime Minister

Verb phrase. Simple clause has a subject and VP, which is a predicate. Each VP - headed by main verb. VP can consist of only verb, dived in the clause He dived, but they also contain dependents (examples in bold):

auxiliaries, e.g. have finished

objects, e.g. bought a bunch of flowers

complements, e.g. grew old

adjuncts, e.g. is leaving tomorrow

AdjP, adjective =head and it can take various dependents. There are dependents (in bold) which are before the head adjective: relatively intelligent, very efficient, any better, this long, no worse; a bit loud, a month late. Dependents stand after head adjective: involved in politics, fond of literature; worth attention, deserving disapproval; worse than she ever imagined, sure that his wife was cheating on him, good enough
AdvP adverb = head. Adverbs like here, now, then, therefore, don’t have dependents; but, most of them can. Examples of dependents (in bold) that typically stand before head adverb are: modifying adverbs, rather quickly; degree adverbs, more efficiently; NP a day late; determiners, that slowly
PP. Prepositions - class of words, express relationships of space, e.g. in the center, or time, e.g. after the meeting. Some prepositions are called multi-word (complex) prepositions. in front of, in between, apart from. PP preposition = head. Head preposition followed by a NP, in the street
Transitive verbs Verb can be transitive or intransitive. Transitive verbs take a direct object that is they express an action which passes on person or thing directly. Verbs like to take, to give, to send, to make, to see, to show, to love. Verbs can be used with or without direct object: to read, to write, to hear, to see. Intransitive verbs cannot take a direct object. Verbs like: as to stand, to sleep, to laugh, to think, to lie, to swim. Transitive verbs classified by number of objects they require. Ditransitive -Verbs that require two objects, a direct object and indirect object. Example of ditransitive verb in English is verb to give, which may have subject, indirect object, and direct object: He told her (indirect object) the truth (direct object). Indirect object occurs only if we have direct object
Subject Important constituents of clause are subject and predicate. In declarative clauses, subject before the verb. Subjects: simple and short: [I] [like cinema] elaborate and long: [The tall guy in a blue shirt whom I was talking to at the party after Barbara’s exam] [is an interior decorator].

Subjects are typically NP, but not always. 1. Her innocence was obvious.

2. That she was innocent was obvious.

3. What she needs is a little respect.

4. To become a good parent takes a lot of patience.

5. Winning the prize made our training worthwhile.

Bolded – subjects, but only 1 one is NP. 2. and 3. - finite clauses, two last are non-finite: a to-infinitive and a present-participle respectively.

Predicate serves to provide info about subject of sentence and it includes head verb, but also include auxiliaries and other elements: complements, objects and adjuncts. Function of head verb in predicate VP called a predicator. In Mary plays the guitar, predicate is VP plays the guitar, and predicator is head verb plays, and in Jill disappeared, both predicate and predicator functions are realised by disappeared.
Complements vs. modifiers, adjuncts, used in sentence to add meaning to it. We can leave out modifiers and adjuncts in given structure, we can’t complements. Complement - constituent (word, phrase, clause), necessary to complete meaning of another constituent. Sentence Put the book on the shelf needs complement on the shelf to be complete. PP on the shelf - complement. But sentence The book on the shelf is boring doesn’t require on the shelf to be complete, here phrase on the shelf is modifier, optional element and can be omitted.
Sentences, clauses. Eng clause - group of words, contains subject and predicate. Clauses: independent (main) clause can stand by itself or dependent, (subordinate) clause, cannot function by itself and needs an independent clause to complete its meaning. Clause can be a sentence (an independent clause) or an element of another sentence (a dependent clause).
Basic types of clauses are:
(statement) e.g. The guests are on time.

open interrogative(information seeking question) When will the guests arrive?

closed interrogative (yes/no question) e.g. Are the guests on time?

exclamative clause (exclamatory statement) e.g. How late the guests are!

imperative clause (command, request) Make sure the guests are on time.

Sentence types 4 sentence types:

simple sentence has single independent clause I don’t drink coffee.
compound sentence built of two or more independent clauses, joined by a coordinating conjunction: and, but, for, or, nor, so, yet, e.g. I don’t drink coffee, and my husband doesn’t drink tea.

Clauses which make up compound sentence are elements with same grammatical status. Coordinated clause can stand on its own.

complex sentence independent clause and has dependent clauses. Dependent clauses (depend on main clause) express additional info about element. Start with subordinating conjunction: that, because, while, where, if, I hate people that stare at me when I go past.
compound-complex sentence contains three or more clauses, of which two are independent and one dependent: I don’t drink coffee, and my husband doesn’t drink tea because it makes him sleepy.
Kernel sentence,‘kernel’stands for central or most important part of anything. In grammar kernel is minimum framework of sentence which expresses a complete thought. Kernel sentence is:
forms a sentence on its own, so it is a simple sentence;
declarative, so it cannot be interrogative, imperative, or exclamative,
kernel sentence is structurally complete, not reduced by ellipsis,
it is positive
it cannot be passive or cleft.

Thematic markedness. Theme - defined as what’s talked about, and comment (rheme) what is being said about the topic. Based on sentence structure, theme - part of sentence that announces item about which rest of sentence communicates information. Phrase identifying the primary theme is at the beginning of clause. In Eng themes – subjects, typically are NP and have semantic role of an actor (agent).
Passive voice If active voice is basic (kernel), we can make passive:

change function of subject, becomes a complement of preposition by. (Resultant phrase by + NP will serve the semantic function of agent);
change function of object so that it becomes a subject;
add verb be (get) in appropriate inflectional form as superordinate to the original verb;
put the original verb into the past participle form.

Extraposition - syntactic process where subordinate clause plays role of subject, moved to position beyond the main predicate. In this process constituents (finite and non-finite clauses) placed at end of sentence. It would be a mistake to change your mind now

When subordinate clause subject is extraposed (moved towards the end of a sentence), sentence is introduced by pronoun it (“dummy” it), to take over vacated subject function: motivation for extraposition: it moves a subordinate clause to end of sentence, making complex and long material to come late in the sentence.

Existential construction involves the use of dummy pronoun there as subject, used to indicate existence: There were some friends at the party. Existential there not a typical subject, it is not a NP, and not personal pronoun. Appears in subject function and occupies a position typical of a subject, namely before the verb in declaratives.
The cleft construction grammatically distinct construction where the cleft sentence is formed by a main clause and a subordinate clause, which are derivable from more elementary clauses by “cleaving”(dividing them into two parts), one of which is highlighted, while the other is subordinated in the form of a relative clause. Together - express a meaning that could be expressed by simple sentence. Cleft sentence can be schematically constructed as:
+ inflected form of be + X + subordinate clause

in which dummy it is a subject, a form of be is a predicator, and the highlighted element (X) is a complement. It is her optimism that makes her so likable