Branching (linguistics)

In linguistics, branching refers to the shape of the parse trees that represent the structure of sentences.

In the constituency-based structures, left-branching is present (but not really visible) in so far as the non-head daughter is to the left of the head.

This right-branching is completely visible in the lower row of dependency-based structures, where the branch extends down to the right.

The head appears in a medial position, which means that the phrase combines both types of branching.

The following trees illustrate what can be seen as a stereotypical combination of left- and right-branching in English: Determiners (e.g. the) always and subjects (e.g. the child) usually appear on left branches in English, but infinitival verbs (e.g. try, eat) and the verb particle to usually appear on right branches.

Despite these conflicting traits, most standard X-bar structures (in English) are more right-branching than left-branching because specifiers tend to be less complex (i.e. fewer words) than complements.

Much work in Government and Binding Theory (GB), the Minimalist Program (MP), and Lexical Functional Grammar (LFG) assumes all branching to be binary.

Spanish, for example, while overwhelmingly right-branching, puts numeral modifiers before nouns and, in certain cases, objects before verbs.

Languages like English or Swedish, though regarded as being right-branching because the main verbs precede direct objects, place adjectives and numerals before their nouns.

On the contrary, Northwest Caucasian languages such as Ubykh or Abkhaz are strongly left-branching but put adjectives after nouns.