Syntactic Tools part 2: Lexical Entries
Once we have learned (using constituency tests) which parts of the sentence constitute each phrase, we can then assign a head. If we know the name of the phrase that we have identified, then finding the head is easy. For example the head of a DP is the determiner, the head of a VP would be the verb. For a complete guide with examples please see the table below:
Each head of a phrase has its own lexical entry, which is stored in our brains in something linguists call a lexicon (like a dictionary). This tells us certain features about the head including where it can be positioned in a sentence. The lexical entry also shows what can/must precede and follow the head (syntacticians call these requirements selection and c-selection, respectively).
If we look at the future tense marker will (this would be the head of the TP), then we can make a lexical entry for it, as follows:
will (future): T, selects DP subject, c-selects VP
So let’s break it down.
- The T tells you that will is a type of T(ense)
- ‘selects DP subject’ shows that the head must be preceded by a DP (the subject of the sentence in this case)
- ‘c-selects VP’ shows that the unit following the T head will be a full VP.
- Notice that the VP is itself a phrasal unit. Heads often select for phrasal complements rather than simple heads because syntax is hierarchical, rather than linear! (See the Constituency section for discussion of this).
The: D, c-selects NP
Wash: V, selects DP subject, c-selects DP
Why do you think that the noun car or the adjective blue don’t select or c-select for anything? Intuitively, what is different about them versus a determiner like the or a verb like wash?