There are 4 sentence structures.
First, it is important to recap what an independent and a dependent clause is.

➜ An independent clause (IC) is a clause that makes sense on its own as a sentence.

➜ A dependent clause (DC) is a clause that doesn’t make sense on its own as a sentence.

Simple sentence

A simple sentence contains one independent clause. This clause contains a subject and a verb.

E.g. The boy jumped.

Compound sentence

A compound sentence contains two independent clauses joined with a coordinating conjunction.
The coordinating conjunctions are: for and nor but or yet so.

E.g. I like to play tennis. I don’t like to play football. These sentences are examples of independent clauses, however, Instead of having two separate clauses, we can combine them using a conjunction.

➜ I like to play tennis, but I don’t like to play football.

Complex sentence

A complex sentence contains one independent clause and at least one dependent clause.

E.g. I passed the exam. ➜ This is an independent clause.

E.g. because I studied very hard ➜ This is a dependent clause.

There are two ways in which we can combine the IC & DC.

➜ When the independent clause comes first; then, a comma is not required to join the independent clause and the dependent clause, so the sentence is: I passed the exam because I studied very hard.

➜ When the dependent clause comes first; then, a comma is required to join the dependent clause with the independent clause, so the sentence is: Because I studied very hard, I passed the exam.

Compound-complex sentence

A compound-complex sentence contains two or more independent clauses, and one or more dependent clauses joined with a coordinating conjunction.
The coordinating conjunctions are: for, and, nor, but, or, yet, & so.

E.g. I baked a cake and I baked some cookies while listening to the radio.