Prototypically, a noun phrase is used as an argument. Although noun phrases may also act as the argument of an adjective or an adposition, the discussion here will be confined to their function as argument of the verb. The fact that noun phrases can be used as arguments is related to the fact that they are typically used to refer to (possibly singleton) sets of entities. As pointed out in 1.1.2, the NP part of the noun phrase provides the descriptive information needed for identifying the set of entities in question, and the DP part determines the referential or quantificational properties of the noun phrase as a whole. These sets of entities function as participants in the state of affairs denoted by the verb; they are assigned the thematic roles of agents, themes, recipients, benefactives etc. by the verb.
      Some examples are given in (16). In the intransitive construction in (16a), the only participant, Jan, performs the action of working and is thus assigned the semantic function of agent. In the transitive construction in (16b), Jan is assigned the same semantic role, but now a second entity is involved, a book, which undergoes the action of buying and is called the theme. In (16c&d), there is a third participant in the state of affairs: in (16c) this third participant, the one receiving the theme entity, functions as the recipient; in (16d), the state of affairs is performed on behalf of a particular entity, which is assigned the role of benefactive. In example (16e) we find a construction with an unaccusative verb; in such constructions the only participant, Jan, receives the semantic function of theme.

The semantic roles are often associated with a particular syntactic function in the clause. The agent is generally the subject of an active clause (16a-d), the theme is typically realized as the direct object (16b-d), and the recipient and benefactive are generally realized as indirect objects (16c&d). It is however certainly not the case that there is a one-to-one mapping between semantic role and syntactic function; for instance, in the case of an unaccusative verb, the theme is realized as the subject (16e), and not as the expected direct object. Since it is neither our aim to give an exhaustive overview in this section of the semantic roles that can be assigned to noun phrases, nor to discuss how these roles can be realized syntactically, we refer the reader to Chapter V2 for more detailed discussion of verb types and the semantic roles they may assign.

Although typically used as arguments, noun phrases also function as predicates, in which case the noun phrase is not used to refer to an entity or a set of entities but to predicate a property of some other noun phrase. Typical cases are found in copular and vinden-constructions, illustrated in (17a&b). In these examples, the noun phrase Jan is the logical subject of the predicatively used noun phrase een aardige jongen: Jan is referential, een aardige jongen is not. The predicative relationship between the two noun phrases is syntactically reflected in that they must agree in number, as is shown by the primed examples; see Section 8.2.2 for one exception to this agreement requirement.

A small number of noun phrases can be used as adverbial phrases modifying the clause. These noun phrases include head nouns that have a temporal denotation, as in examples (18a&b), or that can be used to indicate a period of time, as in example (18c). more or less the same meaning can be conveyed by a PP introduced by gedurende'during'.

However, there are a number of subtle meaning differences between constructions with an adjunct DP and a PP introduced by gedurende. Apart from the fact that the latter is more formal, use of the adjunct DP deze week seems to suggest that Marie has been working hard all week; use of the PP gedurende deze week does not trigger this interpretation (even making it implausible). Furthermore, the period of time referred to may vary. In (18a), the DP deze week refers to the span of time stretching from Monday to Sunday directly preceding or including the speech time, whereas in the case of the PP gedurende deze week reference can also be made to a particular week in the past. Observe that the choice of the demonstrative plays a role here as well: if the proximate demonstrative deze'this' is replaced by the distal demonstrative die'that', the second meaning difference is lost, with both phrases referring then to a particular week in the past (or the future).