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This page pertains to UD version 2.

xcomp: open clausal complement

An open clausal complement (xcomp) of a verb or an adjective is (i) a core argument of the verb, (ii) which is without its own subject and (iii) for which the reference of the subject is necessarily determined by an argument external to the xcomp. The third requirement is often referred to as obligatory control. An xcomp can also be described as a predicative complement. The subject of the xcomp is normally, but not always, controlled by the object of the next higher clause, if there is one, or else by the subject of the next higher clause. These clauses tend to be non-finite in many languages, but they can be finite as well. The name xcomp is borrowed from Lexical-Functional Grammar (see Joan Bresnan, 2001, Lexical-Functional Syntax, chapter on “Predication Relations”).

We expect them to change their minds
xcomp(expect, change)
obj(expect, them)
Sue asked George to respond to her offer
xcomp(asked, respond)
iobj(asked, George)
I started to work there yesterday
xcomp(started, work)
You look great
xcomp(look, great)
I consider him a fool
obj(consider, him)
xcomp(consider, fool)
Louise struck me as a fool
obj(struck, me)
case(fool, as)
xcomp(struck, fool)
I consider her honest
obj(consider, her)
xcomp(consider, honest)
I regard her as honest
obj(regard, her)
mark(honest, as)
xcomp(regard, honest)
We got COVID-19 under control
obj(got, COVID-19)
case(control, under)
xcomp(got, control)
Susan is liable to be arrested
cop(liable, is)
xcomp(liable, arrested)

The predicative complement can be headed by various parts of speech, including a VERB, ADJ, or NOUN. A nominal predicative complement can be marked by a preposition (in English, often but not always by as). The xcomp-taking predicate of the higher clause can be a VERB or ADJ.

Contrast xcomp with other complement clauses where there is an overt subject or no obligatory control, which use ccomp:

He says that you like to swim
ccomp(says, like)
I suggest eating now before the food gets cold
ccomp(suggest, eating)

The Inherited Subject Criterion

In examples like “I consider her honest”, the UD analysis corresponds to traditional grammar and what was termed “raising to object” in early generative grammar: the nominal “her” in these constructions is treated as the object of the higher clause (as its accusative morphology and ability to passivize suggests).

Note that the above condition “without its own subject” does not mean that a clause is an xcomp just because its subject is not overt. The subject must be necessarily inherited from a fixed position in the higher clause. That is, there should be no available interpretation where the subject of the lower clause may be distinct from the specified role of the upper clause. In cases where the missing subject may or must be distinct from a fixed role in the higher clause, ccomp should be used instead, as below. This includes cases of arbitrary subjects and anaphoric control. In the following example, the subject of start or starting does not have to be the boss, it is any contextually relevant person or group of people. In addition, in these cases, the complement clause can often be replaced by a pronoun like it or that and it can sometimes be passivized (Starting the project was recommended by the boss).

The boss said to start the project
ccomp(said, start)
The boss recommended starting the project
ccomp(recommended, starting)

Pro-drop languages have clauses where the subject is not present as a separate word, yet it is inherently present (and often deducible from the form of the verb). The relation between clauses with pro-drop may or may not be xcomp. The implicit subjects of a subordinate clause and a higher clause may be coincidentally coreferent, warranting ccomp or advcl:

Píšu , protože jsem to slíbil . \n I-write , because I-have it promised .
advcl(Píšu, slíbil)
advcl(I-write, promised)
aux(slíbil, jsem)
aux(promised, I-have)
obj(slíbil, to)
obj(promised, it)
mark(slíbil, protože)
mark(promised, because)
Slíbil jsem , že budu psát . \n Promised I-have , that I-will write .
ccomp(Slíbil, psát)
ccomp(Promised, write)
aux(Slíbil, jsem)
aux(Promised, I-have)
aux(psát, budu)
aux(write, I-will)
mark(psát, že)
mark(write, that)

It is only xcomp if the implicit subject depends on an argument from a higher clause (one cannot be varied without the other):

Slíbil jsem psát . \n Promised I-have to-write .
xcomp(Slíbil, psát)
xcomp(Promised, to-write)
aux(Slíbil, jsem)
aux(Promised, I-have)

Secondary Predicates

The following is excerpted from a more detailed discussion of secondary predicates.

The xcomp relation is also used in constructions that are known as secondary predicates or predicatives. Examples:

We could paraphrase the sentence using a subordinate clause: She declared that the cake was beautiful. There are two predicates mixed in one clause: 1. she declared something, and 2. the cake was beautiful (according to her opinion). The secondary predicate will be attached to the main predicate as an xcomp:

She declared the cake beautiful .
nsubj(declared, She)
obj(declared, cake)
xcomp(declared, beautiful)

The subject of “declared” is again obligatorily controlled by a role in the higher clause. In the enhanced representation, there is an additional subject link showing the secondary predication:

She declared the cake beautiful .
nsubj(declared, She)
obj(declared, cake)
xcomp(declared, beautiful)
nsubj(beautiful, cake)

A Czech example:

jmenovat někoho generálem \n to-appoint someone as-a-general
obj(jmenovat, někoho)
xcomp(jmenovat, generálem)

Remember that xcomp is used for core arguments of predicates so it will not be used for non-core instances of secondary predication. For instance, in She entered the room sad we also have a double predication (she entered the room; she was sad). But sad is not a core argument of enter: leaving it out will neither affect grammaticality nor significantly alter the meaning of the verb. On the other hand, leaving out beautiful in she declared the cake beautiful will either render the sentence ungrammatical or lead to a different interpretation of declared.

The result is that in She entered the room sad, sad is considered a modifier (not complement) of the verb, with the relation advcl instead of xcomp. (This was changed from the previous approach which analyzed the secondary predication directly with acl, because the nominal predicand is not always overt, and even when it is, the adjective does not really belong to the same nominal phrase.)

She entered the room sad .
nsubj(entered, She)
det(room, the)
obj(entered, room)
advcl(entered, sad)
punct(entered, .)
Entering the room sad is not recommended .
csubj(recommended, Entering)
det(room, the)
obj(Entering, room)
advcl(Entering, sad)
cop(recommended, is)
advmod(recommended, not)
punct(recommended, .)

Notice that while can be inserted before sad, clearly marking it as a clause.

A Czech example:

Vstoupila do místnosti smutná . \n She-entered to room sad .
advcl(Vstoupila, smutná)
advcl(She-entered, sad)

There is no need to decide whether an example like the following is a depictive or a manner adverbial:

Linda found the money walking our dog .
nsubj(found, Linda)
det(money, the)
obj(found, money)
advcl(found, walking)
det(dog, our)
obj(walking, dog)
punct(found, .)

The optional secondary predication or controlled adjunct subject relation can be represented with an enhanced dependency edge in addition to the advcl relation.

Some other cases that could be regarded as secondary predicates are just treated as obliques. In particular, locative arguments of verbs are always treated as obliques:

She put a book on the table .
nsubj(put, She)
det(book, a)
obj(put, book)
case(table, on)
det(table, the)
obl(put, table)
punct(put, .)

xcomp in other languages: [bg] [bm] [cop] [cs] [de] [el] [en] [es] [eu] [fi] [fr] [fro] [ga] [gsw] [hy] [it] [ka] [kk] [la] [ml] [no] [pa] [pcm] [pt] [qpm] [ru] [sl] [sv] [swl] [tr] [u] [vi] [yue] [zh]