Sentence Structure
The four types of sentences are:
simple	(1 independent clause)	Joe ate the cookie.
compound	(2 independent clauses)	Joe ate the cookie, and he drank his milk.
complex	(1 independent clause and at least 1 dependent clause)	After Joe drank the milk, he jogged a mile. Joe jogged a mile after he drank the milk.
compound-complex	(2 independent clauses and at least 1 dependent clause) dependent clauses sometimes begin with subordinating conjunctions which make them easier to find	After Joe drank the milk, he jogged a mile, and he made a milkshake. Joe jogged a mile, and he made a milkshake after he drank t milk. Joe jogged a mile, and after he drank the milk, he made a milkshake.
subordinating conjunctions
unless until although so that if when after before because as soon as even though wherever whenever whoever how while There are more. You cannot necessarily memorize them all. You must recognize their function in the sentence.
Some dependent clauses are embedded in the independent clauses, and they can be tricky. Noun clauses (which are used as nouns in the sentence) or adjective clauses (which modify nouns) are harder to identify. See the following examples: Joan, who was six in September, started school this year. The girl who told him where to find the office was new herself. Whatever he ate did not agree with him. The donut you took was for my lunch. The version he told (of what you said) did not match the one I head heard. In this case, a noun clause operates as the object of the preposition right after an adjective clause that modifies version.