How Do We Break Down English Grammar?

	“The list divides all animals into 14 categories:
	Those that belong to the emperor  
	Embalmed ones  
	Those that are trained  
	Suckling pigs  
	Mermaids (or Sirens)  
	Fabulous ones  
	Stray dogs  
	Those that are included in this classification  
	Those that tremble as if they were mad  
	Innumerable ones  
	Those drawn with a very fine camel hair brush  
	Et cetera  
	Those that have just broken the flower vase  
	Those that, at a distance, resemble flies”  
				- Jorge Luis Borges

When you are trying to categorize something, sometimes you don't know what you'll end up with.

OK, we have tests for users to take, but how do the users figure out what test to take? Oh, we have tags for this. I produced them quite a long time ago so that we could build UI around them. But do our tags actually help the end users? Do they really do the job?

I was thinking like this when it became clear that they likely don't. Were never designed to. What the tags hierarchy looked like? Well, I believe, I'll do the reader a favor by not presenting it here at all.

It all started with the strange idea that it is possible to somehow use EAQUALS descriptors to index tests.

EAQUALS Descriptors

Initially, I was intending to base our taxonomy on CEFR levels. This is the road that led me to EAQUALS descriptors. A terrific idea? Rather terrible, as I soon understood.

The problem is that the descriptors were never intended to serve as an index for anything. Their purpose is to help with figuring out levels of language mastery instead. This is why their goal is not to describe grammar as a whole, and they may contain duplicates at different CEFR levels, and so on. Anyway here are they, as they are outlined here. Use the mind map to see for yourself. You can pan, zoom in and out the map and collapse and expand the nodes.

See as list...

Descriptors

C2/Proficiency
C1/Advanced
- Inversion with negative adverbials
- Mixed conditionals in past, present and future
- Modals in the past
- Narrative tenses for experience, incl. passive
- Passive forms, all
- Phrasal verbs, especially splitting
- Wish/if only regrets
- Futures (revision)
- Mixed conditionals
- All passives
- Reported Speech and Modal Verbs
- Reported Speech and Conditional Sentences
- Participle vs Gerund
- Conditional Subjunctive
- Conditional Type 2 Subjunctive
- Conditional Type 1 Subjunctive
- Conditional Type 3 Subjunctive
- Intensifiers
- Comparatives
- Superlatives
- Disyllabic Adjectives
- Modifiers
- Irregular Adjectives
- Monosyllabic Adjectives
- Participle Adjectives
- Inversion with Time Adverbials
- Inversion in Conditionals
- Inversion with the subject complement
- Inversion with Negative Adverbial Phrases
- Inversion with Place Adverbials
B2/Upper Intermediate
- Complex Sentence
- Adjectives with Infinitive and Gerund
- Adjectives with Infinitive and Gerund
- Infinitive with passive voice
- Sensing Verbs and Infinitive
- Verbs Followed by Infinitive or Gerund with a Difference in Meaning
- Verbs Followed by Infinitive or Gerund
- Adverb Degrees
- Three Syllable Adjectives
- Transitive and Intransitive Verbs
- Adjectives and adverbs
- Future perfect
- Future perfect continuous
- Modals - can't have, needn't have
- Modals of deduction and speculation
- Narrative tenses
- Passives
- Past perfect continuous
- Relative clauses
- Wish
- Would expressing habits, in the past
- Phonological
- Passive forms
- Conditional forms
- Complex noun phrases
- Collocation of intensifiers
- Adjectives with Three or More Syllables
B1/Intermediate
- 1st and 2nd Modals
- Modals
- Range of verb forms (past, present and future)
- Conditionals
- Comparatives and superlatives
- Will and going to, for prediction
- Modals: must/have to
- Simple passive
- Wh- questions in the past
- as too, enough
- Complex question tags
- Conditionals, 2nd and 3rd
- Connecting words expressing
- cause and effect, contrast etc.
- Future continuous
- Modals - must/can't deduction
- Broader range of intensifiers such
- Modals - might, may, will, probably
- Past perfect
- Past tense responses
- Phrasal verbs, extended
- Present perfect continuous
- Present perfect/past simple
- Reported speech (range of tenses)
- Modals - should have/might have/etc
- Adverbs
- Special Constructions
- Sequence of Tenses in Indirect Speech
- Reported speech
A2/Elementary/Pre-intermediate
- Countables and Uncountables: much/many
- Future Time (will and going to)
- Articles - with countable and uncountable nouns
- Gerunds
- Going to
- Imperatives
- Modals - can/could
- Modals - have to
- Numeral Comparisons
- Articles and other determiners
- Modals - should
- Adverbs of frequency
- Adverbial phrases of time, place and frequency - including word order
- Adjectives - superlative - use of definite article
- Adjectives - comparative, - use of than and definite article
- Participle
- Gerund
- Past continuous
- Prepositions of time (at/on/in)
- Possessives - use of 's, s'
- Prepositional phrases (place, time and movement)
- Prepositions of time: on/in/at
- Present continuous for future
- Present perfect
- Verb + ing/infinitive: like/want-would like
- Wh-questions in past
- Zero and 1st conditional
- Phrasal verbs - common
- Prepositional phrases (time, place and movement)
- Questions Zero and 1st conditionals
- Could (possibility)
- Modals: should Past simple
- Articles - specific member
A1/Elementary/Beginners
- Past simple of "to be"
- Past Simple
- Possessive adjectives
- Possessive s
- Prepositions, common
- Prepositions of place
- Prepositions of time, including in/on/at
- Present continuous
- Present simple
- Pronouns: simple, personal
- Questions
- There is/are
- To be, including question+negatives
- Verb + ing: like/hate/love
- Simple verb forms
- Modals: can/can't/could/couldn't
- Intensifiers - very basic
- Imperatives (+/-)
- I'd like
- Inversion
- Adjectives: common and demonstrative
- How much/how many and very
- common uncountable nouns
- Prepositions and prepositional phrases
- Tenses

Even though I abandoned the idea of using EAQUALS descriptors as tags, we still decided to keep CEFR levels as an independent tags hierarchy.

So, we still need a taxonomy. Where do I begin? That's easy! I'll adopt a sound contemporary grammar. Cambridge Grammar of English Language is a great candidate, isn't it?

Cambridge Grammar of English Language, The

I start reading and soon begin to appreciate how straight the book describes English syntax. The grammar does not prescribe how one should use English but describes how English is used. Sentences are viewed as built from constituents. Clauses are built up from phrases; phrases are comprised of their respective heads and dependents. Different constituents might bear certain grammatical functions under defined circumstances. Places where phrases may occur in sentences depend on the types of their heads.

You can't encounter an 'exception from a grammar rule' there, and there is no Future Perfect Continuous. What you can find are remarks like “we depart from the tradition of English grammar at many points, sometimes quite sharply. For example, in this book, the reader will find nothing of 'noun clauses', 'adjective clauses', or 'adverb clauses' because that traditional distinction in subordinate clause classification does not divide things satisfactorily and we have abandoned it.” More examples? Determinatives aren't adjectives, pronouns are nouns, nouns in prepositional phrases are complements to prepositions and 'will' is a modal like 'can'.

You can refer to the mind map to get the idea. Please note, that I'm neither a linguist nor have really rigorously checked the map. It also has some categories more expanded than others to make a point, e.g. 'verb phrase' node. Nethertheless, if you see that I got something wrong, please, do give me a tip in comment.

See as list...

Grammar

Syntax
- Sentence
  - constituents
- Syntactic categories
  - Lexical categories
    - Noun
      - Case
        Genitive
        Plain
      - Number
        Count
        Non-count
    - Pronoun
      - Case
        Nominative
        Accusative
        Dependent genitive
        Independent genitive
    - Verb
      - Lexical
      - Primary forms
        Preterite
        3rd singular present tense
        Plain present tense
      - Secondary forms
        Plain form
        Gerund-participle
        Past participle
      - Auxiliary
        Negative form
        Be
        - Am
        - Is
        - Are
        - Ascriptive use
        - Specifying use
      - Aspect
      - Mood & modality
        Deontic
        Epistemic
        Dynamic
    - Adjective
    - Adverb
    - Preposition
      - Stranding
    - Determinative
    - Subordinator
    - Coordinator
    - Interjection
  - Phrasal categories
    - Clause
      - Canonical / Non-canonical
        Counterpart
      - Type and illocutionary force
        Declarative
        Closed interrogative
        Open interrogative
        Exclamative
        Imperative
      - Syntactic processes
      - Negation
        Causal / Non-causal
        Clausal / subclausal
        Non-affirmative
      - Position
        Nucleus
        Prenucleus
        Gap
        Co-indexed element
      - Complement
        Subject
        Object
        Predicative
        Prepositional phrase
      - Adjunct
      - Subordinate
        Relative
        Comparative
        Content
        - Declarative
        - Closed interrogative
        - Open interrogative
        - Exclamative
        - Reported speech
      - Relative
      - Comparative
      - Non-finite
        To-infinitival
        Bare-infinitival
        Gerund-participal
        Past-participal
        Verbless
      - Information packaging
        Preposing
        Postposing
        Inversion
        Existential
        Extraposition
        Cleft
        Passive
    - Verb phrase
      - Complement
        External
        Subject
        Internal
        Object
        Predicative
      - Modifier
    - Noun phrase
      - Determiners
      - Number
    - Nominal
    - Adjective phrase
    - Adverb phrase
    - Preposition phrase
    - Determinative phrase
- Deixis
- Anaphora
Grammatical functions
- Subject
- Head
  - Predicate
    - Predicator
  - Fused
- Dependent
  - Internal/external
  - Complement
  - Modifier
  - Determiner
- Non-head constructions
  - Coordination
  - Supplementation
Morphology
- Lexical word formation
  - Word
    - Compounding
    - Derivation
    - Conversion
- Inflectional morphology
  - Lexeme
    - Lexical base
    - Inflection
Punctuation

A great grammar, isn't it? Should we base our taxonomy on it? Well, I have a crouching suspicion that it might not be easy to perceive or comprehend. Sure, it might be the number one choice for an individual of a highly intelligent alien species, but it still might be a little bit too much for even an advanced English learner. There are also other grammars, good and comprehensive.

Gosh, this is depressing! On the other hand, being a non-native speaker, I supposedly have the advantage of being able to say what is not easy to understand. The challenge is thus to obtain a compelling taxonomy. Having one, I will know that it's not too bad. The quest continues.

Why not to try grammar reference books' contents pages? Sounds like a reasonable idea.

English Grammar in Use by Raymond Murphy

The breakdown is based on my faulty interpretation of the contents page of “English Grammar in Use” by Raymond Murphy.

See as list...

Grammar

Present and past
- Present continuous (I am doing)
- Present simple (I do)
- Present continuous and present simple (I am doing and I do)
- Past simple (I did)
- Past continuous (I was doing)
Present perfect and past
- Present perfect (I have done)
- Present perfect continuous (I have been doing)
- Present perfect continuous and simple (I have been doing and I have done)
- How long have you (been) … ?
- For and since / When … ? and How long … ?
- Present perfect and past (I have done and I did)
- Past perfect (I have done)
- Past perfect continuous (I have been doing)
- Have and have got
- Used to (do)
Future
- Present tenses (I am doing / I do) for the future
- (I'm) going to (do)
- Will/shall
- I will and I'm going to
- Will be doing and will have done
- When I do / When I've done / When and If
Modals
- Can, could and (be) able to
- Could (do) and could have (done)
- Must and can't
- May and might
- Have to and must
- Must / mustn't / needn't
- Should
- Had better / It's time …
- Would
- Can/Could/Would you … ? (Requests, offers, permissions and invitations)
If and wish
- If I do ... and If I did ...
- If I knew ... / I wish I knew ...
- If I had known ... / I wish I had known ...
- Wish
Passive
- Passive (is done / was done)
- Passive (be done / been done / being done)
- It is said that ... / He is said to ... / He is supposed to ...
- Have something done
Reported speech
- He said that
Questions and auxiliary verbs
- Questions
  - Do you know where ... ? / He asked me where ...
- Auxiliary verbs (have/do/can etc.) / I think so / I hope so etc.
- Question tags (do you? Isn't it? etc.)
-ing and to
- Verb + -ing (enjoy doing / stop doing etc.)
- Verb + to ... (decide to ... / forget to ... etc.)
- Verb (+ object) + to ... (I want you to ... etc.)
- Verb + -ing or to ...
  - remember / regret etc
  - try / need / help
  - like / would like etc.
- Prefer and would rather
- Preposition (in / for / about etc.) + -ing
- Be / get used to something (I'm used to ...)
- Verb + preposition + -ing (succeed in -ing / accuse somebody of -ing etc.)
- Expressions + -ing
- To ..., for ... and so that ...
- Adjective + to ...
- To ... (afraid to do) and preposition + -ing (afraid of -ing)
- See somebody do and see somebody doing
- -ing clauses (Feeling tired, I went to bed early.)
Articles and nouns
- Countable and uncountable
- Countable nouns with a/an and some
- A/an and
- The
  - school / the school etc.
  - children / the children
  - the giraffe / the telephone / the piano etc., the + adjective
- Names with and without the
- Singular and plural
- Noun + noun (a tennis ball / a headache)
  -'s (your sister's name) and of ... (the name of the book)
Pronouns and determiners
- Myself / yourself / themselves etc.
- A friend of mine / My own house / On my own / by myself
- There ... and it ...
- Some and any
- No/none/any Nothing/nobody etc.
- Much, many, little, few, a lot, plenty
- All / all of most / most of no / none of etc.
- Both / both of neither / neither of either / either of
- All, every and whole
- Each and every
Relative clauses
- Relative clauses
  - who / that / which
  - whose / whom / where
  - extra information clauses
- -ing and -ed clauses (the woman talking to Tom, the boy injured in the accident)
Adjectives and adverbs
- Adjectives ending in -ing and -ed (boring/bored etc.)
- Adjectives: a nice new house, you look tired
- Adjectives and adverbs
  - quick / quickly
  - well / fast / late, hard / hardly
- So and such
- Enough and too
- Quite, pretty, rather and fairly
- Comparison
  - cheaper, more expensive
  - much better / any better / better and better / the sooner the better
  - as ... as / than
- Superlatives (the longest, the most enjoyable etc.)
- Word order
  - verb + object; place and time
  - adverbs with verb
- Still, yet and already and more / any longer / no longer
- Even
Conjunctions and prepositions
- Although / though / even though In spite / despite
- In case
- Unless As long as Provided / providing
- As (As I walked along this street … / As I was hungry ...)
- Like and as
- Like / as if / as though
- For, during and while
- By and until By the time ...
Prepositions
- At / on / in (time)
- On time and in time At the end and in the end
- In / at / on
- To / at / in / into
- In / on / at
- By
- Noun + preposition (reason for, cause of etc.)
- Adjective + preposition
- Verb + preposition
  - to and at
  - about / for / of / after
  - about and of
  - of / for / from / on
  - in / into / with / to / on
Phrasal verbs
- General points
- In / out
- out
- on / off
- up / down
- up
- away / back
Regular and irregular verbs
Present and past tenses
The future
Modal verbs (can / could / will / would etc.)
Short forms (I'm / you've / didn't etc.)
Spelling
American English

As we see, the contents appear to be organized to fulfill the needs of some specific group of learners interested in particular constructs. Usage examples with or instead of grammar categories look very practical: they make it easier for the reader to find his way around. It's a pity that such “category names” end up being too long to serve as tags.

Apparently, it's important that the classification is designed to serve as a contents section of a book. Perhaps, if the author intended it for hypertext, it would differ. Another consequence is that the structure reflects the content of different modules of the book, as contrasted with the grammar of the language.

Looks like another miss. What else? Why not figure out how other people with similar task at hand approach it?

British Council, Supposedly

In the dark depths of my work notes, there was a list. I assume that I somehow produced it using a British Council website, my notes didn't tell me which exactly. I was successful in finding some of the constructions in Google cache but failed to find the source of the whole taxonomy. It might have never existed as a whole. I might have produced it myself based on a menu structure or header or in a like manner. I can't remember, sorry. Still I think it's interesting and worth being mentioned here.

See as list...

Grammar

Adjectives
- adjective order
- adjectives
- as ... as
- comparatives superlatives
- like, as
- much, far, a little, lots + comparatives
- participle adjectives
Adverbials
- adverbial phrases
- adverb position in sentence
- adverbs
- comparative & superlative adverbs
- enough, too, too much
- no, not
- so, such
- still, yet, already
- very, too
Connected discourses
- clauses
- cohesion
- discourse
- exclamations
- linking words - addition
- linking words - cause and effect
- linking words - contrast
- linking words - sequence
- paragraph organisation
- participle clauses
- reference
- relative clauses (who, which, that, whose)
- signposting words & phrases
- substitution & ellipsis
- text organisation
- topic sentences
- word order in sentences
Determiners
- articles (a, an, the, zero)
- demonstratives (this, those)
- determiners
- much, many, a lot, little, few
- some, any, no, someone, anything
- punctuation
Prepositions
- ing after prepositions
- phrasal verbs (prepositions, particles)
- prepositional phrases (place, time)
- prepositional phrases (time, movement)
- prepositions
Pronouns & Nouns
- all, everybody, everything
- countable & uncountable
- impersonal pronouns (one, you, they)
- indefinite pronouns
- ing as subject, object
- noun phrases
- one(s) (big green ones)
- personal pronouns (I, me)
- plurals
- possessives (my, mine)
- possessives (of, 's)
- pronouns & nouns
- pronouns - questions
- pronouns - this, that, these, those
- proper nouns
- reciprocal pronouns
- reflexive pronouns (myself)
- relative pronouns
- use of 'it'
- whoever, no matter who
Verb
- Auxiliary Verbs
  - do (auxiliary)
  - negatives
- Conditionals / Hypotheticals
  - if sentences
  - if sentences: past meaning
  - if sentences: present & future meaning
  - if, unless, in case
  - it's time, would rather
  - wish, if only
- Main Verbs
  - be
  - delexical verbs
  - get structures
  - have
  - have (as main verb)
  - have, have got (possession)
  - imperatives
  - infinitive of purpose
  - infinitives (simple, perfect, ...)
  - infinitives (with, without 'to')
  - irregular verbs
  - link verbs
  - stative verbs
  - there is, are
  - verb patterns
  - verbs with two objects
- Modal Auxiliary Verbs
  - can
  - could
  - had better
  - may, might
  - must, have to
  - need
  - ought to
  - shall
  - should
  - supposed to
  - will
  - will or shall
  - would
- Questions
  - inversion
  - negative questions
  - question tags
  - question words
  - short answers
  - which, what (what size?)
- Tenses Aspects Moods
  - future in the past
  - future perfect
  - future perfect progressive
  - future progressive
  - futures with if & when
  - going to
  - have something done
  - indirect speech
  - infinitive or ing?
  - passive
  - past perfect
  - past perfect progressive
  - past progressive
  - past simple
  - perfect aspect
  - present perfect progressive
  - present perfect simple
  - present progressive
  - present progressive (for future)
  - present simple
  - present simple (for future)
  - progressive aspect
  - since, for
  - used to (past)

This is another classification that helps the reader to find what he or she is after. This might be close to what we need... Actually, for the first time, I have a disturbing feeling that it might be better than whatever we end up with.

Please pardon me for being opinionated, but I would argue that it's not ideal for us. Why? Firstly, it contains too many topics, it's too detailed. Secondly, you will laugh, but it appears to be... not enough theoretical and fundamental to me. You cannot just read CGEL without repercussions, I guess.

Let's try something they use to harass natives in school this time.

English Grammar and Composition by John E. Warriner

See as list...

Grammar

Basic Parts of Speech
- Nouns
- Pronouns
- Adjectives
- Adverbs
- Prepositions
- Verbs
- Interjections
- Conjunctions
- Determining Parts of Speech
Subject and Predicate
- What is a Sentence
- Subject and Predicate
- Finding the Subject of a Sentence
- The Sentence as a Complete Thought
- The Predicate Nominative
- The Predicate Adjective
- Direct and Indirect Objects
Phrases and Clauses
- Prepositional Phrases
- Phrases Used as Adjectives
- Phrases Used as Adverbs
- Participles
- Gerunds
- Infinitives
- Clauses
- Complements and Modifiers
- Sentence Structures

Looks reasonable, even a bit basic. I couldn't get my hands on the actual book this time. Maybe this is why the index is not detailed enough. I'm intending to do it later. For now, it isn't going to serve as a good tags tree for us.

Let's refer to Wikipedia!

Wikipedia

See as list...

Grammar

Word classes and phrases
- Nouns
  - Phrases
  - Gender
- Determiners
  - Common determiners
    - Articles
    - Definite
    - Indefinite
    - Quantifiers
    - Words that enumerate / indicate alternatives
    - Personal determiners
    - Other cases
  - Zero determiner
  - Combinations of determiners
  - Determiners and adjectives
- Pronouns
  - Personal
  - Demonstrative and interrogative
  - Relative
  - "There"
  - Other
- Verbs
  - Inflected forms
    - Principal parts
    - Base form
    - Third person singular present
    - Past tense
    - Past participle
    - Present participle
    - Copular, auxiliary and defective verbs
    - Archaic forms
  - Syntactic constructions
    - Tenses, aspects and moods
      - Simple and progressive
      - Perfect
      - Future and conditional
    - Passive voice
      - Imperatives
      - Questions, negation, inversion and emphasis
  - Use of verb forms
    - Finite forms
    - Non-finite forms
  - Objects and complements
  - Phrasal verbs
  - Phrases
- Adjectives
  - Comparison
  - Phrases
- Adverbs
  - Phrases
- Prepositions
- Conjunctions
- Case
- Declension
  - Number
  - Possessives
Clause and sentence structure
- Word order
- Questions
- Dependent clauses
- Negation
- Imperatives
- Elliptical constructions

What can I say here? It's surprisingly good. I think we could probably go with something like this. My arguments against are:

It's too academic when it comes to terms' names, and the names are too long;
Yet it's rather casual when considered as an index for a grammar;
It has different levels of detail for different topics (which might be my fault);
There are too many terms.

As I don't seem to be able to adopt even a reasonably good taxonomy, the only remaining choice is to roll my own.

Our version

The main goal was to help our users find their way around our content.

~~Cooking up~~ composing our own hierarchy, I followed the principles listed below.

Terms should follow ESL/EFL tradition as opposed to scientific tradition.
Terms should be easily recognizable by non-professionals.

Popularity is more important than precision.
Familiarity is more important than correctness.

The taxonomy should be built from general to specific.
It should be comprehensive enough.
Good, if the terms are granular and orthogonal where applicable.
Smaller is better than larger.

I decided to not recognize syntax as a separate term. It's too academic. After all, who in the world searches for "syntax"? Another discovery was that clear separation of concerns, with parts of speech, clause constituents and grammar functions, leads to CGELish taxonomy in no time. With a heavy heart, I dropped that idea too. Some tags were joined together to fit categorizing test questions e.g., "Countable and uncountable". A number of other lucrative shortcuts were taken.

So, here it is.

See as list...

Grammar

Parts of speech
- Noun and pronoun
  - Noun
  - Pronoun
  - Countable and uncountable
    - Number
  - Case
  - Possessive
  - Person
- Verb
  - Tense
    - Present
      - Historical
    - Past
    - Future
    - Simple
    - Continuous / Progressive
    - Perfect
    - Habitual
  - Mood
    - Indicative
    - Imperative
    - Subjunctive
  - Auxiliary
    - Modal
  - Be
  - Finite
  - Infinitive
  - Irregular
  - Gerund
  - Passive
  - Participle
  - Phrasal
  - Transitive and intransitive
- Adjective and adverb
  - Adjective
  - Adverb
  - Comparative and superlative
- Determinative
  - Article
  - Demonstrative
- Preposition
- Conjunction
- Interjection
- Particle
Sentence and structures
- Clause and sentence
  - Sentence
    - Complex
    - Compound
  - Clause
    - Relative
  - Declarative
  - Interrogative
    - Question
  - Exclamative
  - Imperative
  - Independent
  - Dependent
  - Conditional
- Phrase
- Negation
- Word order
  - Inversion
- Function
  - Subject
  - Predicate
  - Complement
  - Object
  - Modifier
    - Intensifier
  - Determiner
  - Quantifier
  - Coordination
  - Supplementation
  - Argument
- Indirect speech
- Adjunct
- Deixis and anaphora
Morphology
- Word
- Lexeme
Punctuation
- Apostrophe
- Colon
- Comma
- Dash and hyphen
- Elipsis
- Exclamation mark
- Period
- Question mark
- Quotation mark
- Semicolon

The terms are intended to be used as tags which can be combined e.g. if Noun and Phrase tags are used together, this might indicate Noun + Phrase = Noun phrase, or, say, Verb + Present + Perfect + Passive = Verb in present perfect tense and passive voice.

We will update this article to keep up with current understanding of what grammar taxonomy best fits our scenario.
If you notice any error, please leave a comment below. I'll be happy to correct it.

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