function

The three basic functions are substantival, adjectival, and adverbial.   video   A substantive is any word performing a noun function.  The basic noun functions are:

1. subject,
2. object,
3. predicate nominative,
4. apposition.

Adjectival means that word, phrase, or clause is modifying some noun (or pronoun). Adjectival elements in a sentence tend to answer the following questions:

1. what kind?    The oak tree near the house must be removed. (what kind of tree?)
2. which one?    The large book must be burned. (which book?)
3. how many?    Six dogs chased Jeb. (how many dogs?)

Adverbial means that word, phrase, or clause is modifying some verb. Adverbial elements in a sentence tend to answer the following questions:

1. How?     Jeb ran quickly. (Jeb ran how?)
2. when?    Jeb ate his food after sunset. (Jeb ate when?)
3. where?    Jeb slept under the bridge. (Jeb slept where?)
4. why?    Jeb studied to earn his degree. (Why did Jeb study?)