Consists of one independent clause, which is one thought, and no dependent clauses.
What is simple?
300
Consists of two or more independent clauses and one or more subordinate (dependent) clauses.
What is compound-complex?
400
Consists of one independent clause, and one or more subordinate or dependent clauses. Each dependent clause is usually introduced by special introductory words. There are three groups of dependent clause introductory words: subordinating conjunctions, relative pronouns, and noun clause introductory words.
What is complex?
500
Consists of two or more independent clauses joined by a comma and a coordinating conjunction (and, but, or, for, nor, so, yet).