English grammar

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English grammar
Adjectives Adverbs Articles Clauses Compounds Conditionals Conjunctions Determiners Gender Idiom Interjections Inversion Nouns Pronouns Phrases Plurals Possessives Prepositions Verbs Auxiliaries, contractions Irregular verbs Modal verbs Passive voice Phrasal verbs Subjunctive Verb usage Grammar disputes

English grammar is a body of rules specifying how meanings are created in English. There are many accounts of the grammar, which tend to fall into two groups: the descriptivist, which describe the patterns through which meanings are typically created in functional speech and writing; and the prescriptivist, which set out pre-existing rules as to how meanings are created (see prescription and description).

No human language's grammar has been fully mapped out. That is, no set of unambiguous rules has been formulated that will always or usually agree with native speakers on whether any given sentence is grammatical or not. (This is evidenced by the generally poor performance of automated grammar checkers). The development of a complete grammar is an important goal of natural language processing.

The remainder of this article deals with English grammar as viewed from a linguistic perspective. Therefore, the issues addressed deal mainly with the grammars of natural dialects of everyday speech rather than those of formal writing. Issues common to all languages are not stressed here.

Word order

English is a subject verb object (SVO) language: it prefers a sequence of subject–verb–object in its simplest, unmarked declarative statements. Thus, "Tom [subject] eats [verb] cheese [object]" and "Mary sees the cat."

However, beyond these simple examples, word order is a complicated matter in English. In particular, the speaker or writer's point of departure in each clause is a key factor in the organization of the message. Thus, the elements in a message can be ordered in a way that signals to the reader or listener what the message concerns.

The duke has given my aunt that teapot. (i.e., I am going to tell you about the duke).
My aunt has been given that teapot by the duke. (i.e., I am going to tell you about my aunt).
That teapot has been given to my aunt by the duke. (i.e., I am going to tell you about that teapot).

The point of departure can also be set up as an equation, known as a thematic equative. In this way, virtually any element in a clause can be put first.

"What the duke gave my aunt was a teapot" (i.e., I am going to tell you what the duke gave my aunt).
"What happened was that the duke gave my aunt a teapot" (i.e., I am going to tell you what happened).

Usually, the point of departure is the subject of a declarative clause; this is the unmarked form. A point of departure is marked when it is not the subject — thus, occasionally it is the object ("You I blame for this dilemma") and more often an adverbial phrase ("This morning I got up late").

In questions, point of departure is treated slightly differently. English questions come in two types: wh-questions and yes-no questions. Ordinary (unmarked) questions of either type start with the word that indicates what the speaker wants to know.

"Where is my little dog?" (I want you to tell me where.) [wh-question]
"Is John Smith inside?" (I want you to tell me whether he is or is not). [yes-no question]

Special (marked) questions displace this key "what I want to know" word with some other element.

"After tea, will you tell me a story?" (Still "will you or will not you?")
"In your house, who does the cooking?" (Still "who?")

Either imperative clauses are of the type "I want you to do something" or "I want you and me to do something." The second type usually starts with let us; in the unmarked form of the first type, you is implied and not made explicit ("Improve your grammar!"), and included in the marked form ("You improve your grammar!"); another marked form is "Do improve your grammar." In the negative, "Do not argue with me" is unmarked, and "Do not you argue with me" is marked.

In spoken English, the point of departure is frequently marked off by intonation.

Generally, English is a head-initial language, meaning that the "anchor" of a phrase (segment of a sentence) occurs at the beginning of the phrase.

Ran quickly (verb phrase)
To the store ( prepositional phrase)

The main exception is that simple modifiers precede the noun phrases:

A dog (article + noun)
Blue house (adjective + noun)
Fred's cat (possessive + noun) but man of the house (noun + prepositional phrase)

This leads to a sentence like: "Fred's sister ran quickly to the store." As can be inferred from this example, the sequence of a basic sentence (ignoring articles and other determiners as well as prepositional phrases) is: Adjective1 - Subject - Verb - Adverb - Adjective2 - Indirect Object - Adjective3 - Direct Object.

Interrogative sentences invert word order ("Did you go to the store?"). Changing a given sentence from active to passive grammatical voice changes the word order, moving the new subject to the front ("John bought the car" becomes "The car was bought by John"), and lexical or grammatical emphasis (topicalization) changes it in many cases as well (see duke-aunt-teapot examples above).

English also sees some use of the OSV (object-subject-verb) word order, especially when making comparisons using pronouns that are marked for case. For example, "I hate oranges, but apples I will eat." Far more rare, but still sometimes used is OVS, "If it is apples you like, then apples like I," although this last usage can sound contrived and anachronistic to a native speaker.

Nouns

In English, nouns generally describe persons, places, things, and abstract ideas, and are treated as grammatically distinct from verbs. English nouns, in general, are not marked for case or gender, but are marked for number and definiteness.

Gender

A remnant of grammatical gender is also preserved in the third person pronouns. Gender is assigned to animate objects based on biological gender (where known), and to personified objects based on social conventions (ships, for example, are often regarded as feminine in English). He is used for masculine nouns; she is used for feminine nouns; and it is used for nouns of indeterminate gender and inanimate objects. The use of it to refer to humans is generally considered ungrammatical and impolite, but is sometimes used deliberately as a term of offence or insult as it implies the person is of indeterminate gender or, worse, sub-human - a thing. (See for example: A Child Called "It")

Traditionally, the masculine he was used to refer to a person in the third person whose gender was unknown or irrelevant to the context; recently, this usage has come under criticism for supporting gender-based stereotypes and is increasingly considered inappropriate (see Gender-neutral language). There is no consensus on a replacement. Some English speakers prefer to use the slightly cumbersome "he or she" or "s/he", others prefer the use of they (third plural) (see singular they). This situation rarely leads to confusion, since the intended meaning can be inferred from context, e.g. "This person has written me a letter but they have not signed it." However, it still is considered by some to be incorrect grammar. Spivak pronouns have also been proposed which are essentially formed by dropping the leading from the plural counterpart, but their use is relatively rare compared to other solutions. For comparison, speakers of German distinguish between the homophonous sie ("she"), sie ("they"), and Sie ("you", polite) with little difficulty.

The categorization of nouns is typically expressed by one or more of the elements called deictic, numerative, epithet, and classifier. We shall consider each of these in turn.

Deixis

The deictic element indicates whether or not a specific subset of a noun is intended; and if so, which subset. A deictic is either (i) specific or (ii) non-specific. The specific deictics are given in the following table.

	determinative	interrogative
demonstrative	this, these; that, those; the	which(ever); what(ever)
possessive	my, your, our, his, her, its, their, one's, [John's] [my father's], etc.	whose(ever), [which person's] etc.

The subset in question is specified by one of two possible deictic features: either

(a) demonstratively, i.e., by reference to some kind of proximity to the speaker
- ("this", "these" = "near me"; "that", "those" = "not near me"), or
(b) by possession, i.e., by reference to 'person' as defined from the standpoint of the speaker
- ("my", "your", "our", "his", "her", "its", "their"; also "Mary's", "my father's", etc.)

Together with the possibility of an interrogative in both of these categories (demonstrative "which?" and possessive "whose?"). All of these have the function of identifying a particular subset of the noun that is being referred to.

"Proximity to the speaker" refers not only to physical distance, but also to temporal; deictics orient the listener to the 'speaker-now', the temporal–modal complex that constitutes the point of reference of the speech event. Therefore, "this tragedy" refers to one that is current or recent and/or is or was geographically close to the speaker, whereas "that tragedy" refers to one that occurred in the past and/or was less geographically close.

There is one more item in this class, namely "the". The word "the" is a specific, determinative deictic of a peculiar kind: it means "the subset in question is identifiable; but this will not tell you how to identify it—the information is somewhere around, where you can recover it"; typically, the listener/reader can recover the information from assumed general knowledge, the specific context, or from a specific and recent point in the text. So whereas "this train" means "you know which train: the one near me", and "my train" means "you know which train: the one I own", "the train" means simply "you know which train." Hence "the" is usually accompanied by some other element that supplies the information required: for example, "the long train" means "you know which train: you can tell it by its length."

Non-specific deictics convey the sense of all, or none, or some unspecified subset. The main categories and main items in each are as follow.

(a) Total

positive ("each", "every", "both", "all")
negative ("neither", "no", i.e. "not any")

(b) Partial

selective ("one", "either", "some", "any")
non-selective ("a" or "an", "one")

There are two systems of number for English nouns, one associated with each of the two kinds of deictics. (i) With specific deictics, the number system is non-plural versus plural; mass nouns are grouped together with singular, in a category of non-plural. Therefore "this" and "that" go with non-plural (singular or mass), and "these" and "those" go with plural.

For example, for non-plural nouns, singular might be "this train" (plural "these trains") and mass might be "this electricity" (no plural equivalent).

(ii) With non-specific deictics, the system is singular versus non-singular. Therefore, "a" and "an" go with singular and weak "some" with non-singular (mass or plural).

For example, "a train" is singular (plural "trains" or "some trains"); non-singular mass ("electricity" or "some electricity" has no singular equivalent).

If there is no deictic element, the noun is non-specific and, within that, non-singular. In other words, a noun may have no deictic element in its structure, but this does not mean that it has no value in the deictic "system", but simply that the value selected is realized by a form having no deictic in the expression.

Number

English nouns are typically inflected for number, having distinct singular and plural forms. The plural form usually consists of the singular form plus -s or -es, but there are many irregular nouns. Ordinarily, the singular form is used when discussing one instance of the noun's referent, and the plural form is used when discussing any other number of instances, but there are many exceptions to this rule. Examples include:

The girl (singular) talks.
The girls (plural) talk.
Every girl (singular) talks.
All girls (plural) talk.
No girl (singular) talks.
No girls (plural) talk.

Articles

A definite article such as "the" is used to refer to a specific instance of the noun, often already mentioned in the context or easy to identify. Definite articles are slightly different from demonstratives, which often indicate the location of nouns with respect to the speaker and audience.

"Let us look for a good restaurant."
"What about the restaurant we ate at last week?"
"That restaurant was terrible. What about this one on the corner here?"

An indefinite article such as "a" or "an" is used to refer to a generic instance of the noun. Note that "a" is used when preceding a noun beginning with a consonant sound, whereas "an" is used when preceding a noun beginning with a vowel sound.

You should have a drink.
That building is a university.
They are being an annoyance.
He is an heir to the throne.

However, "a" and "an" can function as definite articles as well; in some constructions, they will be used to emphasize the singularity of the subject. For example:

A single teardrop fell from her eye.
An anteater crossed the otherwise lonely road.

Case

Historically, English used to mark nouns for case, and the two remnants of this case marking are the pronominal system and the possessive clitic (which used to be called the Saxon genitive). The possessive is marked by a clitic at the end of the possessing noun phrase. This can be illustrated in the following manner:

The king's daughter's house fell.

The first 's clitic on king indicates that the daughter in question is the king's. The second 's clitic does not attach to daughter, as many people mistakenly believe, but in fact to the entire noun phrase The king's daughter.

English preserves the old Germanic noun case system in its pronouns. Their forms vary with gender, number, person, and case. The full set of cases is listed below; note that modern use of the second person singular thou, originally the informal form to the formal you, is very rare, and is confined to dialects and religious and poetic functions. In modern Standard English, the second person plural you is used instead.

Case	1st sg.	2nd sg.	3rd sg.	1st pl.	2nd pl.	3rd pl.	interrogative
Nominative	I	you (thou)	he, she, it	we	you (ye)	they	who
Genitive	mine/my	yours/your (thine/thy)	his, hers/her, its	ours/our	yours/your	theirs/their	whose
Reflexive	myself	yourself (thyself)	himself/herself, itself	ourself	yourselves	themselves	who
Accusative	me	you (thee)	him, her, it	us	you	them	whom

Notes

Some dialects use different forms for the second person plural pronoun: they include you-all or y'all , you guys, yu'uns , youse , or ye . These forms are generally regarded as colloquial and non-standard.
The pronoun thou was the former second person singular pronoun; it is considered an archaism in most contexts, although it is still used in some dialects in the north of England.
Mine (and thine) were also previously used before vowel sounds to avoid a glottal stop. e.g., "Do mine eyes deceive me?” "Know thine enemy." This usage is now archaic.
Whom is often replaced with who.

See English personal pronouns, for further information.

Nouns as other parts of speech

Nouns can also be used as verbs, as in "verbing weirds language", or as adjectives, as in "mountain bike". See the following articles:

Verbification
Adjective: Adjectival use of nouns

Verbs

In English, verbs generally describe actions, and can be used to describe certain states of being. In contrast to the relative simplicity of English nouns, verbs come in a large array of tenses, some moods, two voices, and are marked for person.

Person

Verbs in English are marked in limited fashion for person. Unlike some other European languages, person cannot generally be inferred from the conjugation attached to the verb. As a result, subject nouns and pronouns are generally required elements in English sentences for clarity's sake. Most regular verbs in English follow the paradigm exemplified below for the simple present of the verb "to listen":

1st sg.	I listen	1st pl.	We listen
2nd sg.	You listen	2nd pl.	You listen
3rd sg.	He/she/it listens	3rd pl.	They listen

Note: an archaic version of the second person singular is "thou listenest", and of the third person singular "he/she/it listeneth".

Tense

Changes in tense in English are achieved by the changes in ending and the use of auxiliary verbs "to be" and "to have" and the use of the auxiliaries "will", "shall" and "would". (These auxiliaries cannot co-occur with other modals like can, may, and must.) The examples below use the regular verb to listen:

Present tenses
- Simple present (or simply "present"): "I listen." This tense expresses actions in the present on a habitual or repetitive basis, but not necessarily happening now as the speaker is speaking.
- Present continuous (or "present progressive"): "I am listening." This tense expresses actions in the present taking place as the speaker is speaking.
- Present perfect: "I have listened." This tense expresses actions that began in the past but are still true in the present: "I have known her for six years" (and I still know her).
- All forms of the present tense are often used in place of their future-tense counterparts. In particular, various kinds of subordinate clauses — especially if and when clauses — cannot generally use the future tense, so the present tense is used instead.
Past tenses
- Simple past: "I listened." This is used to express a completed action that took place at a specific moment in the past. (Confusingly, in US English, the simple past may sometimes be used for a non-specific moment in the past).
- Present perfect or perfect "I have listened." This is used to express a completed action that took place at a non-specific moment in the past. This tense often expresses actions that happen in the past, yet cannot be considered a past tense because it always has a connection to the present.
- Past continuous (otherwise known as the imperfect or past progressive): "I was listening." This is used to express an incomplete action in the past. (Thus an "imperfect" action, as opposed to a completed and therefore "perfect" action.)
- Past perfect or pluperfect: "I had listened." This expresses an action completed before some other action in the past (often expressed by the simple past). The pluperfect is thus expressing an action even more in the past e.g. "He realised he had lost his way", "I was going to town because he had spoken to me".
- Present perfect continuous: "I have been listening." This is used to express that an event started at some time in the past and continuing to the present.
- Past perfect continuous or simply "perfect continuous": "I had been listening." Usually used with an explicit duration, this indicates that an event was ongoing for a specific time, e.g. "When Peter entered my room, I had been listening to music for half an hour."

Future tenses
- Simple future: "I shall/will listen." This is used to express that an event will occur in the future, or that the speaker intends to perform some action.
- Future continuous: "I shall/will be listening." This is used to express an ongoing event that has not yet been initiated.
- Future perfect: "I shall/will have listened." This indicates an action which will occur before some other action in the future: Normally two actions are expressed, and the future perfect indicates an action which will occur in the future but will, at the time of the main future action expressed, be in the past (e.g. "I will know the tune next week because I will have listened to it").
- Future perfect continuous or future imperfect: "I shall/will have been listening." Expresses an ongoing action that occurs in the future, before some other event expressed in the future.
- "I am going to listen" is a construction using "to go" as an auxiliary. It is referred to as going to future, futur proche or immediate future, and has the same sense as the simple future, sometimes with an implication of immediacy. It is not strictly a tense, and "to go" is not strictly a tense auxiliary verb, but this construction often presented as a tense for simplicity. By varying the tense of the auxiliary "to go", various other meanings can be achieved, i.e. I am going to be listening (future continuous), I was going to listen (Conditional perfect continuous).

Conditional tenses
- Present conditional or simply conditional: "I would listen." This is used to express an event that occurred multiple times or was ongoing in the past (i.e. When I was younger, I would listen. [multiple times]), or something that would be done now or in the future when predicated upon another condition (i.e. “If I had the time, I would listen to you.” [This condition could be known from context and omitted from the conditional statement.])
- Present continuous conditional: "I would be listening." This is used to express an ongoing event that had not yet been initiated.
- Conditional perfect: "I would have listened." Indicates that an action would occur after some other event.
- Conditional perfect continuous: "I would have been listening": Expresses an ongoing action that would occur in the future in the past, after some other event.

Auxiliary verbs may be used to define tense, aspect, or mood of a verb phrase.

As mentioned above " going to" is used for some future pseudo-tenses:

Forms of "do" are used for some negatives, questions and emphasis of the simple present and simple past:

"Do I listen?" "I do not listen." "I do listen!"
"Did I listen?" "I did not listen." "I did listen!"

Verb tense chart

English verb tenses can be better visualized in the following chart, which shows the times of the English language and its three aspects, namely Prior, Complete and Incomplete. Note that this chart only represents actions truly happening, be it present, past or future. Since unreal conditionals are obviously assumptions, conditional structures with 'would' are not included here.

	PAST	PRESENT	FUTURE
PRIOR ASPECT	Past Perfect	Present Perfect	Future Perfect
COMPLETE ASPECT	Simple Past	Simple Present	Simple Future
INCOMPLETE ASPECT	Past Continuous	Present Continuous	Future Continuous

Voice

English has two voices for verbs: the active and the passive. The basic form is the active verb, and follows the SVO pattern discussed above. The passive voice is derived from the active by using the auxiliary verb "to be" and the past participle form of the main verb.

Examples of the passive:

Passive voice	Active voice
I am seen by John	John sees me
You will be struck by John	John will strike you
It was stolen by John	John stole it
We were carried by John	John carried us
They have been chosen by John	John has chosen them

Furthermore, the agent and patient switch grammatical roles between active and passive voices so that in passive the patient is the subject, and the agent is noted in an optional prepositional phrase using by, for example:

active: I heard the music.
passive: The music was heard (by me). (Note: me, not I)

The passive form of the verb is formed by replacing the verb with to be in the same tense and aspect, and appending the past participle of the original verb. Thus:

Tense	Active voice	The same sense, expressed with the passive voice
Simple present	I hear the music.	The music is heard by me.
Present progressive	I am hearing the music.	The music is being heard by me.
Past progressive	I was hearing the music.	The music was being heard by me.
Past perfect	I had heard the music.	The music had been heard by me.
Simple future	I will hear the music.	The music will be heard by me.

This pattern continues through all the composite tenses as well. The semantic effect of the change from active to passive is the depersonalisation of an action. It is also occasionally used to topicalize the direct object of a sentence, or when the agent is either unknown or unimportant even when included, thus:

The plane was shot down.
Dozens were killed.
Bill was run over by a bus.

Many writing style guides including Strunk and White recommend minimizing use of the passive voice in English; however, many others do not.

There is a third 'voice' in English, related to the classic "middle" voice. In this, the patient becomes the subject, as in passive, but the verb remains in apparently active voice, no agent can plausibly be supplied, and generally, an adverbial modifies the entire construction. Thus:

She does not frighten easily.
This bread slices poorly.
His novels sell well.

Mood

English has "moods" of verb. These always include the declarative/indicative and the subjunctive moods, and normally the imperative is included as a mood. Some people include conditional or interrogative forms as verbal moods.

Indicative, or declarative, mood

The declarative mood or indicative mood is the simplest and most basic mood. The overwhelming majority of verb use is in the indicative, which may be considered the "normal" form of verbs, with the subjunctive as an "exceptional" form of verbs. (If any other forms are considered a mood (e.g. imperative), they may also be considered other "exceptional" verb forms.)

Examples are most commonly used verb forms, e.g.:

I think
I thought
He was seen
I am walking home.
They are singing.
He is not a dancer.
We are very happy.

Subjunctive mood

The subjunctive mood is used to express counterfactual (or conditional) statements, and is often found in if-then statements, and certain formulaic expressions. It is typically marked in the present tense by the auxiliary "were" plus the present participle (<-ing>) of the verb.
1. Were I eating, I would sit.
2. If they were eating, they would sit.
3. Truth be told...
4. If I were you... I would do that.

The conjugation of these moods becomes a significantly more complex matter when they are used with different tenses. However, casual spoken English rarely uses the subjunctive, and generally restricts the conditional mood to the simple present and simple past. A notable exception to this is the use of the present subjunctive in clauses of wish or command which is marked in one or two ways: (1) if third person singular, the "-s" conjugation called for by the declarative mood is absent, and (2) past tense is not used. For example, "They insisted that he go to chapel every morning" means that they were requiring or demanding him to go to chapel. However, "They insisted that he went to chapel every morning" means they are reasserting the statement that, in the past, he did attend chapel every morning. The underlying grammar of this distinction has been called the "American subjunctive". On the other hand, other constructions for expressing wishes and commands, which do not use the subjunctive, are equally common, such as "They required him to go..."

Imperative mood

The imperative mood is used for commands or instructions. It is not always considered a verbal mood per se. Using the verb in its simplest, unconjugated form forms it: "Listen! Sit! Eat!" The imperative mood in English occurs only in the second person, and the subject ("you") is generally not expressly stated, because it is implied. When the speaker gives a command regarding anyone else, it is still directed at the second person as though it were a request for permission, although it may be a rhetorical statement.
1. Let me do the talking.
2. Let us build a bridge.
3. Give him an allowance.
4. Let sleeping dogs lie.

Conditional forms

Conditional forms of verb are used to express if-then statements, or in response to counterfactual propositions (see subjunctive mood, above), denoting or implying an indeterminate future action.

Conditionals may be considered tense forms but are sometimes considered a verbal mood, the conditional mood.

Conditionals are expressed through the use of the verbal auxiliaries could, would, should, may and might in combination with the stem form of the verb.

He could go to the store.
You should be more careful.
I may try something else.
He might be heading north.

Note that for many speakers "may" and "might" have merged into a single meaning (that of "might") that implies the outcome of the statement is contingent. The implication of permission in "may" seems to remain only in certain uses with the second person, e.g. "You may leave the dinner table."

Two main conditional tenses can be identified in English:

I would think = Present Conditional

I would have thought = Conditional Perfect

Interrogative word order

Interrogative word order is used to pose questions, with or without an expected answer. Most of the time, it is formed by switching the order of the subject and the auxiliary (or "helping") verb in a declarative sentence, as in the following:

Are you going to the party?
Is he supposed to do that?
How much do I owe you?
Where is the parking lot?

However, when the information being requested would be the subject of the answer, the word order is not inverted, and the interrogative pronoun takes the place of the subject, as in the following:

Who helped you with your homework?
What happened here?

When spoken, an intonation change is often used to emphasize this switch, or can entirely reflect the interrogative mood in some cases (e.g. "John ran?"). The interrogative phrase can further be formed in this manner by moving the predicate of a declarative sentence in front of the helping verb and changing it to a demonstrative, relative pronoun, quantifier, etc. Ending the sentence with a question mark denotes the interrogative phrase .

Rhetorical questions can be formed by moving the helping verb-subject pair to the end of the question, e.g. "You would not really do that, would you?"

Irregular verbs

While many verbs in English follow the relatively simple paradigm illustrated at the beginning of this section, some verbs do not. There are two categories of such verbs:

strong verbs (the "transparently irregular")
true irregular verbs.

The term "transparently irregular" is sometimes used to describe Jacob Grimm's "strong" verbs that appear irregular at first, but actually follow a common paradigm. This group of verbs is a relic of the older Germanic ablaut system for conjugation. This is generally confined to atypical simple past verb forms, e.g.:

I swim ~ I swam ~ I have swum

I sing ~ I sang ~ I have sung

I steal ~ I stole ~ I have stolen

Another category of "transparently irregular" verbs dates back to Middle English. Some verbs, especially those with a stem ending in an alveolar consonant (/t/, /d/, or /s/), formed a geminate consonant or consonant cluster with the -d suffix. In Middle English, vowels before a consonant cluster often became shorter. As the Great Vowel Shift obscured the connection between long vowels and the corresponding short vowels, transparent irregularities such as the following arose:

I meet ~ I met ~ I have met

I lead ~ I led ~ I have led

I read ~ I read ~ I have read

I lose ~ I lost ~ I have lost

I keep ~ I kept ~ I have kept

True irregular verbs have forms that are not predictable from ablaut rules. The most common of these in English is the verb "to be." A sampling of its verbal paradigm is listed below; the majority of other forms are predictable from the knowledge of these four.

Tense	1st sg.	2nd sg.	3rd sg.	1st pl.	2nd pl.	3rd pl.
Simple present	I am	You are	He/she/it is	We are	You are	They are
Simple past	I was	You were	He/she/it was	We were	You were	They were
Present progressive	I am being	You are being	He/she/it is being	We are being	You are being	They are being

Irregular verbs include eat, sit, lend, and keep, among many others. Some paradigms are based on obsolete root words, or roots that have changed meaning. Others are derived from old umlaut patterns that changes in phonemic structure and grammar have distorted (keep ~ kept is one such example). Some are unclear in origin, and may date back to Proto-Indo-European times.

Adjectives and adverbs

Adjectives are modifiers for nouns and adverbs are modifiers for verbs, adjectives, and other adverbs. Not all languages distinguish them, but English does in both grammar and word formation. Grammatically, adjectives precede the noun they modify, whereas adverbs might precede or follow the verb they modify, depending upon the specific adverb (although there are a small number of exceptions). English also has a means of converting adjectives into adverbs: the addition of the suffix <-ly> changes an adjective to an adverb (in addition to moving it to the appropriate place in a sentence).

Occasionally, people use adverbs with verbs that require an adjective.

"I feel badly" - the speaker has an impaired sense of touch (likewise: "I hear badly")
"I feel bad" - the speaker is ill or upset (likewise: "I feel happy")

The latter is, of course, the meaning most people try to convey. It is unclear whether this example shows the misuse of adjectives/adverbs or the common use of "feel" as a copula verb (whose complement refers to its subject). That is, "feel" is often used with a meaning very close to "be." "I feel sick" is the equivalent of "I am sick" and using "I feel sickly" would be odd, for most native speakers. A better example might be something like: "I drive decent", with a meaning of "I drive decently" or "I drive well."

As well, confusion often occurs between good, well (adj.), and well (adv.).

"I feel good" - a good mood
"I feel well (adj.)" - good health (though this is often replaced by "I feel good" in everyday speech with little ambiguity in meaning)
"I did well (adv.)" - success

There are other ways of changing words from one lexical class to another. Nouns are easily transformed into verbs by moving them to the appropriate position in a sentence, and then conjugating them according to the default paradigm. Nouns can also be changed to other kinds of nouns (<-er>, <-ist>), into adverbs of state/condition (<-ness>), and into adjectives (<-ish>, as in "bullish"). Verbs can be turned into adjectives with <-ing> ("dancing school"), into adverbs with <-ly>, and sometimes even into nouns with <-er> ("dancer", "listener").

These processes provide the English language with greater flexibility in choosing words, expanding vocabulary, and re-shuffling words to add subtlety of meaning that might otherwise not be available in an analytic language.