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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 a predicative or clausal complement without its own subject. The reference of the subject is necessarily determined by an argument external to the xcomp (normally by the object of the next higher clause, if there is one, or else by the subject of the next higher clause). This is often referred to as obligatory control. 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.

He says that you like to swim
ccomp(says, like)
Sue asked George to respond to her offer
xcomp(asked, respond)
obj(asked, George)
You look great
xcomp(look, great)
I started to work there yesterday
xcomp(started, work)
I consider him a fool
xcomp(consider, fool)
I consider him honest
xcomp(consider, honest)
We expect them to change their minds
xcomp(expect, change)
obj(expect, them)

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.

The boss said to start digging
ccomp(said, start)

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) and it does not depend on arguments from a higher clause. Thus in neither of the following two Czech examples is there any overt subject, yet only the second example contains an xcomp.

Píšu , protože jsem to slíbil . \n I-write , because I-have it promised .
advcl(Píšu, slíbil)
advcl(I-write, promised)
Slíbil jsem psát . \n Promised I-have to-write .
xcomp(Slíbil, psát)
xcomp(Promised, to-write)

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)

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 clausal predicates so it will not be used for other 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 will depend on She and the relation will be acl instead of xcomp.


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