Independent or main clause has a subject and a verb and it expresses a complete thought.
~Mount Everest is in the Himalayas
A compound sentence is made up of two or more independent clauses joined by a conjunction
~The Himalayas is a region of high peaks, and it is a region of valleys
Subordinate or dependent clause has a subject and a verb but does not express a complete thought
~ Where they climbed ~Although it is cold
Adjective Clauses
Is a subordinate clause that functions as an adjective. It modifies a noun or a pronoun. It follows the word it modifies.
~Mrs. Garcia, who is my neighbor, is a chef. ~She is the chef whom I most respect.
Some words that introduce adjective clauses are ~Relative Pronouns
That, which, whom, those, who, whose
~ Relative Adverbs
When, where
Can sometimes omit words. An expression that omits words is elliptical. The sentence makes sense with or without the word that introduces the adjective clause
~Have you ever tried the empanadas [that] this restaurant is famous for?
When an adjective clause is essential to the meaning of a sentence, it provides information that is necessary to understand the sentence. Commas don’t separate them.
When an adjective clause is nonessential, it adds information that is not necessary, and the sentence can stand alone without it. Commas separate them.
Adverb Clauses
is a subordinate clause that functions as an adverb. It modifies a verb, an adjective, or another adverb. They tell how much, how, when, where, why, to what extent, or under what circumstances. A comma always follows an introductory adverb clause.
~ The house is quiet when it is empty. [The clause modifies the adjective quiet; it tells when it is quiet]
~ Gail arrived much later than she had planned. [The clause modifies the adverb later; it tells how much later]
Some common subordinating conjunctions are after, although, as, as if, as long as, as much as, as soon