Commas & Semicolons
Use a comma and coordinating conjunction (for, and, nor, but, or, yet, or so) to join two independent clauses (complete sentences).
He wanted to work, but no job was available.
Independent, + coordinating conjunction + independent
No comma is used when joining a dependent clause or phrase with a conjunction.
He wanted to work but could not find a job.
Independent + coordinating conjunction + dependent (no subject)
When starting with a subordinating conjunction, use a comma after the dependent clause.
Because he could not find a job, he was unable to pay his rent.
The subordinating conjunction because makes the first part dependent.
A semicolon can be used to fix a run-on sentence; it is used to join clauses without a conjunction.
Semicolons can be used to connect two related sentences; however, sometimes you may need to use a subordinating conjunction (like however).