The tectogrammatical level is based on the concept of dependency.
The basic idea of the dependency conception is that a dependent elementis determined by its governing element, which stands for the entire collocation (the governing part has the syntactic distribution identical to the entire combination of the governing and the dependent part). Dependency is reflected in morphological form of the dependent part (by agreement of morphological categories between the dependent and the governing part, or by a restriction on the case selection of the dependent part). In accordance with some new syntactic approaches the verb is considered the core of a sentence and the subject is dependent on the verb.
Representing dependency in a tectogrammatical tree . The dependency relation between two elements in a tectogrammatical tree is primarily indicated by an edge between two nodes that runs from the node representing the governing element (governing node) to the node representing its dependent element (dependent node).
PDT tectogrammatical trees differ from dependency trees in the strict sense, in which each edge represents a dependency relationship between two elements and in which each dependency is represented by an edge; namely, in the following:
the second dependency with predicative complements (expressed by an attribute of type reference; see Section 1.1, "Dual dependency");
existence of non-dependency edges (see Section 1.2, "Non-dependency edges"),
cases of ambiguous dependency in which an edge between two nodes does not reflect exact dependency relations within a sentence (see Section 1.3, "Ambiguous dependency").
These specific cases show how complicated dependency relations within particular sentences are. The relations between individual elements in a sentence cannot always be interpreted as simple dependency relations.