Sentences and their Constituents
Apart from the explication given above, we could also claim that sentences consist of strings of words arranged and organised in a particular way. If they are organised according to the rules of a grammar (as represented in a ‘typical’ grammar book), they are claimed to be grammatical or well-formed, or ungrammatical or ill-formed, as shown in the next example:
*the killed the students linguists
(* is a conventional notational sign indicating ungrammatical or ill-formed sentences)
In contrast, the following string of words is deemed to be grammatical.
The students killed the linguists
Note that the same words can be arranged in a different way, thus producing another well-formed sentence:
The linguists killed the students
Linguists are interested in syntactic structures that underlie sentences, and in devices (i.e. phrase-structure rules) used to describe strings of words. All sentences are made up of smaller units called constituents (i.e. unit-forming words), if these units occur next to each other and are in some way related.
To clarify the matters, consider the following example:
The students killed the linguists?
What are the principal constituents of the sentence?
In this case, we can divide the sentence into two main immediate constituents (i.e. ICs): the students and killed the linguists. The result, in turn, can be subdivided into further constituents; thus, the string killed the linguists can be divided into two smaller constituents: killed and the linguists, the strings the students and the linguists into the plus students and the plus linguists, respectively. Finally, the main verb killed can be broken down into kill and the past tense inflectional marker –ed, but we will disregard this option in the following. Constituents that cannot be divided any further are called ‘ultimate constituents’ (i.e. UCs).