Thus far you have been working with sentences and have learned to identify the "subject / (finite) verb / complement patterns" in them. You have also learned that adjectives, adverbs, and most prepositional phrases modify (and thus chunk to) the words in the S/V/C slots. You have probably noticed that many sentences have more than one S/V/C pattern. To be able to discuss these multiple patterns in a sentence, we need to distinguish between "sentence" and "clause."
What Is a Clause?
Because you can already identify S/V/C patterns and distinguish finite verbs from verbals, you will probably find clauses easy to understand. There are two types of clauses, main and subordinate.
Every main clause could be punctuated
as a separate sentence, but just as we compound subjects, verbs, etc.,
we also compound main clauses. Thus you will often find more than one main
clause in a sentence. Although short main clauses can be combined with
commas (I came, I saw, I conquered.), most main clauses are joined
together with the following punctuation:
The differences in these punctuation marks are explored in KISS Level 3.1.1 ("Main Clauses"). They will also be explored in later sections on style and logic. For now, all you need to remember is that when a clause begins with one of them, you are probably dealing with compound main clauses.