English clause syntax


This article describes the syntax of clauses in the English language, that is, the ways of combining and ordering constituents such as verbs and noun phrases to form a clause.

Types of clause

Clauses can be classified as independent and dependent. A typical sentence consists of one independent clause, possibly augmented by one or more dependent clauses.
An independent clause is a simple sentence. Sentences can be classified according to the purpose or function of the sentence into declarative, interrogative, exclamatory sentence or imperative.
In interrogative main clauses, unless the subject is or contains the interrogative word, the verb precedes the subject: Are you hungry? Where am I?. However such inversion is only possible with an auxiliary or copular verb; if no such verb would otherwise be present, do-support is used.
In most imperative clauses the subject is absent: Eat your dinner! However imperative clauses may include the subject for emphasis: You eat your dinner!. The form of the verb is the base form of the verb, such as eat, write, be. Modal verbs do not have imperative forms. Negation uses do-support, even if the verb is be; see below. The imperative here refers to second-person forms; constructions for other persons may be formed periphrastically, e.g. Let's go; Let them eat cake.
A dependent clause may be finite, or non-finite. Particular types of dependent clause include relative clauses, content clauses and adverbial clauses.
In certain instances, clauses use a verb conjugated in the subjunctive mood; see English subjunctive.
Clauses can be nested within each other, sometimes up to several levels. For example, the sentence I know the woman who says she saw your son drinking beer contains a non-finite clause within a content clause within a relative clause within an independent declarative clause.

Non-finite clauses

A non-finite clause is one in which the main verb is in a non-finite form, namely an infinitive, past participle, or -ing form ; for how these forms are made, see English verbs.
The internal syntax of a non-finite clause is generally similar to that of a finite clause, except that there is usually no subject. The following types exist:
In certain uses, a non-finite clause contains a missing item – this may be an object or complement of the verb, or the complement of a preposition within the clause. Examples of uses of such "passive" [|non-finite clauses] are given below:
For details of the uses of such clauses, see below. See also English passive voice.

Constituents of a clause

English is an SVO language, that is, in simple declarative sentences the order of the main components is subject–verb–object.
A typical finite clause consists of a noun phrase functioning as the subject, a finite verb, followed by any number of dependents of the verb. In some theories of grammar the verb and its dependents are taken to be a single component called a verb phrase or the predicate of the clause; thus the clause can be said to consist of subject plus predicate.
Dependents include any number of complements, and other modifiers of the verb. Noun phrase constituents which are personal pronouns or the pronoun who are marked for case, but otherwise it is word order alone that indicates which noun phrase is the subject and which the object.
The presence of complements depends on the pattern followed by the verb. A given verb may allow a number of possible patterns.
Some verbs can take two objects: an indirect object and a direct object. An indirect object precedes a direct one, as in He gave the dog a bone. However the indirect object may also be replaced with a prepositional phrase, usually with the preposition to or for, as in He gave a bone to the dog.
Adverbial adjuncts are often placed after the verb and object, as in I met John yesterday. However other positions in the sentence are also possible; see, and for "phrasal" particles, Phrasal verb. Another adverb which is subject to special rules is the negating word not; see below.
Objects normally precede other complements, as in I told him to fetch it. Other possible complements include prepositional phrases, such as for Jim in the clause They waited for Jim; predicative expressions, such as red in The ball is red; subordinate clauses, which may be introduced by a subordinating conjunction such as if, when, because, that, for example the that-clause in I suggest that you wait for her; and non-finite clauses, such as eating jelly in the sentence I like eating jelly.
Many English verbs are used together with a particle and with preposition phrases in constructions that are commonly referred to as "phrasal verbs". These complements often modify the meaning of the verb in an unpredictable way, and a verb-particle combination such as give up can be considered a single lexical item. The position of such particles in the clause is subject to different rules from other adverbs; for details see Phrasal verb.
English is not a "pro-drop" language – that is, unlike some languages, English requires that the subject of a clause always be expressed explicitly, even if it can be deduced from the form of the verb and the context, and even if it has no meaningful referent, as in the sentence It is raining, where the subject it is a dummy pronoun. Imperative and non-finite clauses are exceptions, in that they usually do not have a subject expressed.
Adjuncts are constituents which are not required by the main verb, and can be removed without leaving behind something ungrammatical. Adjuncts are usually adverbs or adverbial phrases or clauses.
Many clauses have as their finite verb an auxiliary, which governs a non-finite form of a lexical verb. For clauses of this type, see below.

Variations on SVO pattern

Variations on the basic SVO pattern occur in certain types of clause. The subject is absent in most imperative clauses and most non-finite clauses. For cases in which the verb or a verb complement is omitted, see.
The verb and subject are inverted in most interrogative clauses. This requires that the verb be an auxiliary or copula. The same type of inversion occurs in certain other types of clause, particularly main clauses beginning with an adjunct having negative force, and some dependent clauses expressing a condition. For details see subject–auxiliary inversion and negative inversion.
A somewhat different type of inversion may involve a wider set of verbs ; see subject–verb inversion.
In certain types of clause an object or other complement becomes zero or is brought to the front of the clause: see.

Clauses with auxiliary verbs

In many English clauses, the finite verb is an auxiliary verb, whose complement is some type of non-finite clause. For example, in the clause he is eating his dinner, the finite verb is the auxiliary is, whose complement is the participial clause eating his dinner. In some cases the non-finite clause itself has an auxiliary as its main verb, with another embedded non-finite clause as complement. For example:
Here eating his dinner is the complement of been, and been eating his dinner is the complement of has.
The form of each lexical or auxiliary verb is determined by the auxiliary preceding it. The first auxiliary is conjugated as a finite verb in present or past tense: the modals are invariant, but the other auxiliaries may take the forms have, has, had, am, is, are, be, was, were, do, does, did. have, being, or
The principal auxiliaries and the verb forms they govern are:
A modal verb, if present, comes first. Any other auxiliaries come in the order listed above, namely perfect have followed by progressive be followed by passive be. The auxiliary do is not used in combination with any other auxiliary. Otherwise, the above auxiliaries can be used in any combination.
A clause containing the maximum number of auxiliaries might therefore be I will have been being operated on for six hours. Here the modal will is the finite verb; perfect have is in bare infinitive form, progressive be is in the past participle form been, passive be is in the present participle form being, and the lexical verb is in the past participle form operated.
Constructions of this type serve a variety of functions, including the expression of aspect, voice and modality. The meaning of combinations of these auxiliary verbs are presented in more detail [|later in this article].
Some of these constructions are described, particularly in teaching contexts, as tenses – for example, is eating is represented as the "present progressive tense" of eat. The series of auxiliaries and non-finite verb form is treated as a unit. Thus in the examples above, the strings is eating and has been eating may be presented as forms of the verb eat, with his dinner serving as their object.
Non-finite constructions exist for combinations of auxiliary verbs other than the modals verbs or do:
The verbs ought and used differ from other modals in that they require the to-infinitive rather than the bare infinitive: He ought to go; We used to go. There are certain other auxiliary-like expressions that are variously classified:
In interrogative and relative clauses, wh-fronting occurs; that is, the interrogative word or relative pronoun is brought to the front of the clause: What did you see? ; The man to whom you gave the book....
Fronting of various elements can also occur for reasons of focus; occasionally even an object or other verbal complement can be fronted rather than appear in its usual position after the verb, as in I met Tom yesterday, but Jane I haven't seen for ages.
In certain types of non-finite clause, and in some relative clauses, an object or a preposition complement is absent. For example, in I like the cake you made, the words you made form a reduced relative clause in which the verb made has zero object. This can produce preposition stranding : I like the song you were listening to; Which chair did you sit on?

Negation

A clause is negated by the inclusion of the word not:
Certain clauses display ellipsis, where some component is omitted, usually by way of avoidance of repetition. Examples include:
For more analysis and further examples, see Verb phrase ellipsis.

Meanings of clauses using auxiliary verbs

Overview

The various constructions with auxiliary verbs can be used to express aspect, voice and modality.
English clauses can be described as having progressive aspect, perfect aspect, neither, or both. They can also be described as having active voice or passive voice. The following table shows these combinations:
The constructions given above are third-person singular present indicative. However, by changing the form of the finite verb in each case, equivalent forms can be constructed for other persons and numbers, for past tense, and for imperative and subjunctive mood.
The meanings of the aspects are as follows:
Modal verbs can also be used, such as "will" used as above in future constructions and "would" in conditional constructions. These serve as uninflected auxiliary verbs, even in the third person singular. Most of these have multiple modal uses, depending on context. With the exception of ought, all are followed by the short form of the main verb's infinitive. Dare and need, are infrequently used as modals and are much more frequently used instead as main verbs that are inflected with -s in the present tense third person singular; when they are used as main verbs, the infinitive following them includes the particle to.
This is illustrated in the table below with the modal might.
ModalPerfectProgressivePassiveLexical verb
mighttake
mightbetaken
mightbetaking
mightbebeingtaken
mighthavetaken
mighthavebeentaken
mighthavebeentaking
mighthavebeenbeingtaken

The modals are invariant, so in this case it is not possible to inflect for tense or mood. There are no imperative or non-finite forms.
The modal will, in some of its uses, expresses future time. Hence constructions using will as the modal in the above schema are often referred to as being instances of a future tense. Thus forms like will take can be called the simple future, will have taken the future perfect, and so on. Analogous terminology is used for the forms with would ; these are referred to as conditional forms. Sometimes shall and should are also used in this way: see shall and will.

Simple constructions

The simple constructions can be used to express habitual action. In many contexts they can also be used to express single completed actions.
AffirmativeNegativeInterrogativeNegative interrogative
PresentHe writesHe does not writeDoes he write?Does he not write? / Doesn't he write?
PastHe wroteHe did not writeDid he write?Did he not write? / Didn't he write?
Future He will writeHe will not writeWill he write?Will he not write? / Won't he write?
Conditional He would writeHe would not writeWould he write?Would he not write? / Wouldn't he write?

The passive voice is formed using the appropriate form of the verb be followed by the past participle of the main verb, e.g. "He is written."

Present

The simple present has three main uses in English: First, it often identifies habitual or customary action referring to no specific time frame:
Second, it is used with stative verbs to refer to a present situation:
Third, it can have a future meaning in two contexts :
The simple present has an intensive or emphatic construction with "do": He does write. In the negative and interrogative constructions, of course, this is identical to the non-emphatic constructions. It is typically used as a response to the question Does he write, whether that question is expressed or implied, and says that indeed, he does write.
The different syntactic behavior of the negative particle not and the negative inflectional suffix -n't in the interrogative constructions is also worth noting. In formal literary English of the sort in which contractions are avoided, not attaches itself to the main verb: Does he not write? When the colloquial contraction -n't is used, this attaches itself to the auxiliary do: Doesn't he write? This in fact is a contraction of a more archaic word order, still occasionally found in poetry: *Does not he write?'''

Past

The simple past is also called the preterite.
The preterite is used for the English simple past tense. He wrote two more chapters about the dam at Kashagawigamog Lake.
This tense is used for a single event in the past, for past habitual action, and in chronological narration. Like the present simple, it has an emphatic variant with "do": he did write.
The simple past is distinct from the present perfect:
The preterite, when used to indicate habitual aspect, can often be replaced by a compound construction:
English does not have a dedicated future tense in the sense of a morphological form that always indicates what the speaker views as facts about the future.
Shall can be used in place of will: see the article Shall and Will for a discussion of the two auxiliary verbs used to form the simple future in English.
Will and would can be used with a different meaning to futurity or conditionality:
The will construction can be used to indicate what the speaker views as facts about the future:
It can also indicate a combination of futurity and intentional or volitional modality:
It can also indicate predictive modality — what the speaker intends as predictions about the future:
The will construction is occasionally used for statements about the present to indicate that they are speculative:
The will construction can be used to indicate strong volition in the present in the first person:
It can also be used to indicate habituality in the past, present and future:
There is also a future with "go" which is used with the infinitive of the action verb especially for intended actions and for the weather, and which is generally more common in colloquial speech:
The will/shall construction can be used for spontaneous decisions:

Present subjunctive

This form is always identical to the infinitive. This means that apart from the verb to be, it is distinct from the indicative present only in the third person singular and the obsolete second person singular.
It is used to express wishes about the present or future:
It can be used to express present doubt, especially after if, whether, and lest and in set phrases:
The subordinate conjunction whether can be replaced by inversion of be and the subject:
It is also used in a mandative sense:
The present subjunctive can be written in the passive voice as in

Conditional

The conditional present is formed by combining the modal auxiliary would with the infinitive of the main verb:
The conditional present is used principally in a main clause accompanied by an implicit or explicit doubt or "if-clause"; it may refer to conditional statements in present or future time:
Some varieties of English regularly use would in if clauses, but this is often considered non-standard: If you'd leave now, you'd be on time. Such use of would is widespread especially in spoken US English in all sectors of society, but these forms are not usually used in writing that is more formal. Nevertheless, some reliable sources simply label this usage as acceptable US English and no longer label it as colloquial.
There are exceptions, however, where would is used in British English too in seemingly counterfactual conditions, but these can usually be interpreted as a modal use of would: If you would listen to me once in a while, you might learn something. In cases in which the action in the if clause takes place after that in the main clause, use of would in counterfactual conditions is however considered standard and correct usage in even formal UK and US usage: If it would make Bill happy, I'd give him the money.
The auxiliary verbs could and might can also be used to indicate the conditional mood, as in the following:

Progressive constructions

constructions denote ongoing activity at a specific point of time or continuous activity over an extent of time. All verbal constructions can be made progressive, and these constructions are very common. Progressive constructions are also known as "continuous".
AffirmativeNegativeInterrogativeNegative interrogative
PresentHe is writingHe is not writingIs he writing?Is he not writing? / Isn't he writing?
PastHe was writingHe was not writingWas he writing?Was he not writing? / Wasn't he writing?
Future He will be writingHe will not be writingWill he be writing?Will he not be writing? / Won't he be writing?
Conditional He would be writingHe would not be writingWould he be writing?Would he not be writing? / Wouldn't he be writing?

The passive voice of the progressive is formed by the present progressive of to be followed by the past participle of the main verb, e.g. "He is being written."

Present

An important difference between the present progressive tense in English and many other languages with similar tenses is that the English present progressive must be used in many circumstances. In particular, a statement about an ongoing action at the present time normally must use the progressive. The simple present is used in the following circumstances:
In the latter cases, the progressive is often possible, sometimes with different implications. Generally, it implies an action rather than a state, and an ongoing, often temporary situation. For example, "I am feeling lonely" and "I am seeing a bear" specifically emphasize the perception of the feeling at the current time, which is implied to be temporary.
With "have" and "be" the present progressive is even clearer in imparting a meaning of "currently ongoing action". Hence "??I am having a large car" would sound quite strange, and be almost uninterpretable, while "?I am being a doctor" still sounds strange but potentially might mean "I'm not a doctor but I'm temporarily trying to act like one". But there are a number of quite acceptable usages of progressive "have" and "be":
This construction describes the simple engagement in a present activity, with the focus on action in progress "at this very moment". It too can indicate a future, particularly when discussing plans already in place: I am flying to Paris tomorrow. Used with "always" it suggests irritation; compare He always does that with He is always doing that.
Word order differs here in the negative interrogative between the more formal is he not writing and the colloquial contraction isn't he writing?

Past

The past progressive construction indicates ongoing action in the past
This construction is typically used for two events in parallel:
It can also be used for an interrupted action :
Further, it can be used to indicate continuing action at a specific time in the past:
It can also be used to refer to past action that occurred over a range of time and is viewed as an ongoing situation:

Future

This construction is used especially to indicate that an event will be in progress at a particular point in the future: This time tomorrow I will / shall be taking my driving test.
The passive construction It will be being written is rarely used. If it is desired to express future progressivity in the passive voice, the construction It will be in the process of being written can be used.

Conditional

The conditional present progressive is used for the continuous aspect of the conditional construction; it describes a situation that would now be prevailing had it not been for some intervening event:
The passive voice of the conditional present progressive can be formed as It would be being written, but since this construction is awkward the form It would be in the process of being written would be more common.

Perfect constructions

Perfect constructions are used to express actions or events that happened before a point in time, with an emphasis on the continuing effects of these at this point of time.
The following table shows examples of perfect constructions being used with the pronoun "he":
AffirmativeNegativeInterrogativeNegative interrogative
PresentHe has writtenHe has not writtenHas he written?Has he not written? / Hasn't he written?
PastHe had writtenHe had not writtenHad he written?Had he not written? / Hadn't he written?
Future He will have writtenHe will not have writtenWill he have written?Will he not have written? / Won't he have written?
Conditional He would have writtenHe would not have writtenWould he have written?Would he not have written? / Wouldn't he have written?

The passive voice is formed with by the present perfect of to be followed by the past participle of the main verb, e.g. "He has been written."

Present

The present perfect was traditionally just called the perfect.
The distinction between the past and the present perfect can be subtle. In general, the present perfect occurs in cases where there is an explicitly or implicitly established present frame of reference. When the frame of reference is explicit, such as in the sentence "Whenever I get home, usually John has already arrived", the usage of the present perfect is clear, but in other cases it is less obvious.
This construction indicates that a past event has one of a range of possible relationships to the present. This relationship may involve a focus on present result: He has written a very fine book. Alternatively, it may indicate a period which includes the present: I have lived here since my youth. Compare: Have you written a letter this morning? with Did you write a letter this morning?. The perfect construction is frequently used with the adverbs already or recently or with since clauses. The present perfect can identify habitual and continuing actions, continuous and ongoing actions, or completed actions that still affect the present situation.
In addition to these normal uses where the event is viewed from the present, the “have done” construct is used with a future perspective in temporal clauses where other languages would use the future perfect: When you have written it, show it to me.
The term "perfect" was first applied in discussions of Latin grammar, to refer to a tense which expresses a completed action. It was then applied to a French tense which has a similar use to the Latin perfect, and then was transferred to the English tense which looks morphologically something like the French perfect. In fact, the English perfect is often used precisely in situations where Latin would use the imperfect — for past actions which are not finished but continue into the present.
''Have got''
In colloquial English, particularly British English, the present perfect of the verb get, namely have got or has got, is frequently used in place of the simple present indicative of have when denoting possession, broadly defined. For example:
Note that in American English, the form got is used in this idiom, even though the standard past participle of get is gotten.
The same applies in the expression of present obligation: I've got to go now may be used in place of I have to go now.
In very informal registers, the contracted form of have or has may be omitted altogether: I got three brothers.

Past

The past perfect is also known as the pluperfect; it is formed by combining the preterite of to have with the past participle of the main verb:
The past perfect is used when the action occurred in the past before another action in the past. It is used when speaking of the past to indicate the relative time of two past actions, one occurring before the other; i.e. a "past before the past".
The past time of perspective could be stated explicitly:
or it can be understood from previous information:
The past time of perspective can simply be implied by the context:
It is sometimes possible to use the simple past instead of the past perfect, but only where there is no ambiguity in the meaning. For instance, the second example above could be written:
Understood within the above context, this still means that I first invited Jim then later ate the meal.
However, concurrent past events are also possible, indicated by dual simple past tenses in both verbs. Consider the following:
This means both past events happened at the same time: he left at the same time as we arrived.
The past perfect can also be used to express a counterfactual statement about the past:
Here, the first clause refers to an unreal state in the past, and the entire construction is a conditional sentence.

Future

The future perfect is formed by combining, in this order, will or shall, the auxiliary verb have, and the past participle of the main verb. It indicates an action that either is completed sometime prior to a future time of perspective or an ongoing action that continues to a future time of perspective:

Conditional

The conditional perfect construction is used for conditional situations occurring in the past; it expresses thoughts which are or may be contrary to present fact:
Some varieties of English regularly use would have in if clauses, but this is often non-standard: If you 've told me, we could've done something about it. Such use of would is widespread especially in spoken US English in all sectors of society, but is incorrect and is not usually used in more formal writing.
There are exceptions, however, where would is used in British English too in seemingly counterfactual conditions, but these can usually be interpreted as a modal use of would: If you would have listened to me once in a while, you might have learned something. In cases in which the action in the if clause takes place after that in the main clause, use of would in if clauses is however considered standard and correct usage in even formal UK and US usage: If it would have made Bill happy, I'd have given him the money.

Perfect progressive constructions

Perfect progressive constructions are used to express ongoing activity that extends to a certain point in time.
AffirmativeNegativeInterrogativeNegative interrogative
PresentHe has been writingHe has not been writingHas he been writing?Has he not been writing? / Hasn't he been writing?
PastHe had been writingHe had not been writingHad he been writing?Had he not been writing? / Hadn't he been writing?
Future He will have been writingHe will not have been writingWill he have been writing?Will he not have been writing? / Won't he have been writing?
Conditional He would have been writingHe would not have been writingWould he have been writing?Would he not have been writing? / Wouldn't he have been writing?

For passive voice clauses, the present participle is replaced with "being" followed by the past participle.

Present

It is used for unbroken action in the past which continues right up to the present. I have been writing this paper all morning.
The present perfect progressive is used for denoting the action which was in progress and has just finished or is still going on.
For example,
Sentences referring to an expanse of time use the present perfect continuous if ongoing action is referred to. For example,
However, with stative verbs, or if the situation is considered permanent, the present perfect non-progressive construction is used.
For example,
Thus, if the whole period is referred to, for is used, but when the reference is to the starting point of the action, since is used.
The construction It has been being written, while following the usual pattern for the formation of the passive voice, is very rarely used. Occasionally, when it is desired to express the receiving of an action in the past and continuing to the present, the phrasal construction It has been in the process of being written is used. Here the present perfect construction is applied to to be, and the continuity and the passive voice are applied to the main verb in non-finite form in a noun phrase.

Past

The past perfect progressive is also known as the pluperfect progressive , the past perfect continuous, and the pluperfect continuous. It is formed by combining, in this order, the preterite of to have, the past participle of to be, and the present participle of the main verb.
The past perfect progressive relates to the past perfect as the present perfect progressive relates to the present perfect.
The construction It had been being written is very rarely used. To convey the past perfect progressive in the passive voice, the construction It had been in the process of being written can be used.

Future

The future perfect progressive, also called the future perfect continuous, is formed by combining, in this order, will or shall, the auxiliary have, the past participle been, and the present participle of the main verb.
This construction is used for an event that will still be in progress at a certain point in the future: By 8:00 he will have been writing for five hours.
The construction It will have been being written is never used. The construction It will have been in the process of being written can be used to indicate the continuous receiving of an action prior to some time in the future.

Conditional

Rather than the very rarely used awkward construction It would have been being written, the conditional perfect progressive can be expressed in the passive voice as in It would have been in the process of being written.

Subjunctive constructions

Past subjunctive

The past subjunctive is used to express hypotheses about the present or future: it is used to describe unreal or hypothetical conditions. It consists of the verb were in all persons and numbers, either as the main verb or as a helping verb combined with the infinitive of the main verb.
It usually appears in "if clauses" of conditional sentences.
Examples include:
Especially in formal usage, if may be omitted and the order of the subject and were inverted:
When if means when then the indicative is used. Compare
The imperfect subjunctive is also used in "that clauses" after a wish:
This last example can be contrasted with I want her to be here, in which the indicative rather than the subjunctive is used because there is a substantial possibility that the hypothesis is true.
The imperfect subjunctive can be written in the passive voice as in
or

Future subjunctive

A future subjunctive for use in "if clauses" can be constructed using the conjugated form of the verb "to be" plus the infinitive or by using the modal auxiliary verb "should" :
These constructions can alternatively be expressed with inversion of the order of were or should and the subject, with if omitted:
If the were to construction is used in the "if clause", the word would is used in the main clause; if the should form is used in the "if clause", either will or would can be used in the main clause, depending on whether the event is very hypothetical or is quite possible.
The passive voice can be applied to the future subjunctive as in any of the following:
or

Uses of non-finite constructions

The various types of non-finite clauses described above have a number of uses besides the constructions with auxiliaries already described.

Infinitive

An infinitive phrase begins with the base form of the verb. Infinitive phrases can be viewed as part of finite clauses where they are introduced in verb catenae by an auxiliary verb or by a certain limited class of main verbs. They are also often frequently introduced by a main verb followed by the particle to. Further, infinitives introduced by to can function as noun phrases, or even as modifiers of nouns. The following table illustrates these environments:
An infinitive phrase begins with the bare form of the first verb, and is usually co-ordinated by the word "to":
When the semantic agent of the verb phrase occurs as the object in the co-ordinating clause, "to" does not occur:
Infinitive phrases are used after particular verbs such as "want" or "need".
The placement of an adverbial modifier directly after the to of an infinitive phrase is called a split infinitive, and is sometimes regarded as a grammatical or stylistic error.

Present participle and gerund

A present participle phrase uses the present participle form of the verb, ending in "-ing".
It may be used in progressive constructions:
The present participle may be used in non-finite constructions such as the following:
The present participle form of a verb may function as a noun, in which case it is referred to as a gerund. Gerunds typically appear as subject or object noun phrases, or even as the object of a preposition:
Often distinguishing between a gerund and a progressive active participle is not easy; the line between the two non-finite verb forms is not clear.
A present participle may function as an adjective modifying a noun, in which case it is known as a gerundive: "The dancing girls".

Past participle

The past participles of strong verbs in Germanic languages are irregular ; their form is idiosyncratic. The past participles of weak verbs, in contrast, are regular; their form is formed with the suffix -ed.
Past participles are used in perfect and passive constructions:
Past participles occur in a rare construction in English which may be compared with the ablative absolute construction in Latin:
As with present participles, past participles may function as adjectives: "the burnt logs".