A sentence can consist of one independent clause.
A sentence can consist of more than one independent clause (joined by conjunctions).
A sentence can consist of one or more independent clauses and one or more dependent clauses.
An independent clause can be a sentence.
A dependent clause cannot be a sentence.
Every sentence must have at least one independent clause.
Another name for an independent clause is "main clause".
Another name for a dependent clause is "subordinate clause".
CJ