Final answer:
Functional and lexical words can be differentiated through syntactic analysis by assessing the grammatical purpose or specific meaning they carry within a sentence. Functional words structure the sentence, whereas lexical words can take on various morphological forms and carry content.
Step-by-step explanation:
To differentiate between functional and lexical words, we can use a process of syntactic analysis. Functional words are those that have a grammatical purpose in a sentence, such as articles, prepositions, conjunctions, and pronouns, while lexical words carry specific meanings and include nouns, adjectives, verbs, and adverbs. Since functional words are more about connecting and structuring the sentence rather than adding new content, they usually do not change form, while lexical words can often be modified and take on different morphological forms.
An example of syntactic analysis in determining word classes can be seen in the sentence 'Eating an apple a day can keep the doctor away, or so they say.' Here, traditionally the word 'eating' would be identified as a verb due to its form, but syntactically, it functions as a noun because it is the subject of the sentence. Similarly, 'Jose' is a proper noun by form, but in the phrase 'Jose's mother,' it functions adjectivally to describe whose mother is being referred to.