In syntax, units larger than morphemes, such as phrases and sentences, are isolated in manner that reflects a hierarchical structure; thus the sentence "My sister Mary slowly took the cake from the shelf" would have as primary constitutents "My sister Mary" and "slowly took the cake from the shelf." Each primary constituent then may be broken down into a series of hierarchical secondary constituents. The analysis of syntax is also concerned with the ordering of the grammatical sequences within the phrase, with agreement between concomitant entities (i.e., agreement of number and gender between subject and verb, noun and pronoun), and with case, as mandated by the position and function of a word within a sentence. Other aspects of syntax include such sentence transformations as negativization, interrogation, coordination, subordination, passivization and relativization.
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