Answer:
1a. a word or group of words containing a noun and functioning in a sentence as subject, object, or prepositional object.
1b. Thing expressions are basically things with modifiers. Fair as things can act as subjects, objects, and prepositional objects, so can thing expressions. Additionally, thing expressions can moreover work in a sentence as descriptive words, participles, infinitives, and prepositional or supreme expressions. The modifier can come some time recently or after the thing.
1c. determiners, adjective phrases, noun adjuncts, attributive adjectives.
1d. The head or nucleus of a phrase is the word that determines the syntactic category of that phrase.
