A compound sentence is when two independent clauses are joined by a co-ordinating conjunction: and, but, or, for, yet, so
EX: I like coffee, and he likes tea.
EX: I like coffee, but I don't like latte.
EX: Does she like coffee, or does she like tea?
EX: I like coffee, so I am going to order a coffee.
EX: I like coffee, yet I think I will order tea instead.
A compound sentence is made up of two independent clauses:
1) I like coffee. (independent clause)
2) He likes tea. (independent clause)
=> I like coffee, and he likes tea. (compound sentence)
A complex sentence is made up of an independent clause and a dependent clause. Depedent clauses begin with a subordinating conjunction,
as long as
in order that
Only complex sentence have dependent clauses. Dependent clauses begin with a subordinating conjunction:
EX: After she left, I did the dishes.
EX: When you go to the store, could you pick up some milk?
EX: He wants me work because he needs extra people.
EX: Could you show me so that I can understand?
A complex sentence is made up of an independent clause and a dependent clause,
1) After she left. (dependent clause. It begins with "After", a subordinator)
2) I did the dishes. (independent clause)
==> After she left, I did the dishes. (complex sentence)
==> I did the dishes, after she left. (complex sentence)
There are also complex-compound sentences:
After she left, Mary went to sleep and I did the dishes.
1) After she left. (Dependent clause)
2) Mary went to sleep. (Independent clause)
3) I did the dishes. (Independent clause)
Note that, the subordinating conjunction "After" tells us that "After she left" is a dependent clause, and that the co-ordinating conjunction "and" tells us that there are two independent clauses.