名词 dog 是短语 big red dog 的中心语，因为它决定了短语的句法范畴，使该短语成为一个名词短语（英语：noun phrase），而不是形容词短语。形容词 big 和 red 是用来修饰（英语：Grammatical modifier）中心语的，故称为依存语（英语：dependent (grammar)）。[5] 类似地，合成词 birdsong 中词干 song 是中心语，因为它决定了整个词的基本意义。词干 bird 是 song 的依存语。Birdsong 是一种 song，而不是一种 bird。反过来 songbird 就是一种 bird。
^head - Oxford Advanced Learner's Dictionary. oxfordlearnersdictionaries.com. [20 July 2022]. （原始内容存档于2021-05-06）. the central part of a phrase, which has the same grammatical function as the whole phrase.
^Jack C. Richards, Richard Schmidt, Heidi Kendrick, Youngkyu Kim；管燕红，唐玉柱译．朗文语言教学与应用语言学词典（第3版）．北京：外语教学与研究出版社，2005：304．
^Discerning heads from dependents is not always easy. The exact criteria that one employs to identify the head of a phrase vary, and definitions of "head" have been debated in detail. See the exchange between Zwicky (1985, 1993) and Hudson (1987) in this regard.
^For a good general discussion of heads, see Miller (2011:41ff.). However, take note Miller miscites Hudson's (1990) listing of Zwicky's criteria of headhood as if these were Matthews'.
^Dependency grammar trees similar to the ones produced in this article can be found, for instance, in Ágel et al. (2003/6).
^Using the words themselves as the labels on the nodes in trees is a convention that is consistent with bare phrase structure (BPS). See Chomsky (1995).
