• Changing complex sentences to compound sentences mostly involves flipping complex sentences around. The following examples combine two equal sentences, but instead of using coordinating conjunctions with a comma to join the two independent clauses, a subordinating conjunction is used to combine them instead in each example. When a subordinating conjunction is used in this manner, there is no subordinate clause. Just like with coordinating conjunctions, then, each sentence could stand alone as an independent clause. A comma is not needed when subordinating conjunctions are used to join independent clauses.