Can I have examples of complex sentences

Example: Whenever prices goes up, customers buy less products.

This sentence is an example to something that happens "after" which needs to have a comma to separate the dependent clause. The verb "go" and subject "prices" makes it a complete sentence.

For example; He sang and she danced. There are seven coordinating conjunctions that enable two clauses to be equal and they are worth taking the time to memorise; A complex sentence has one independent clause and at least one dependent clause. ur welcome