Commas in Compound Sentences

Use a comma before a coordinating conjunction in a compound sentence.

A compound sentence consists of two or more independent clauses, often joined by a coordinating conjunction (for, and, nor, but, or, yet, so--fanboys)

The one area in which I had experienced the most difficulty during my high school years was
Algebra so I was careful to avoid anything having to do with math.

Crost, Mary Lou. "Math Anxiety." The Harper Anthology. Palatine: William Rainey Harper College, 1994. 28-31.

My home away from home was my hotel room in West Berlin and my suitcase was my only companion. . .The thought of a long bath, some TV and then shut-eye really appealed to me but I had to see what was happening at the Berlin Wall. . . All the spotlights were on and I had never seen so many people in front of the crossover. . . I did not realize that I was crying until a total stranger hugged me and I saw that she was crying too. One Trabbi* [*Trabant, an East German-built, 2-cylinder, plastic car] after the other was crossing over the border, the border which seemed to have been closed forever.

Klugstedt, Christian J. "History." The Harper Anthology. Palatine: William Rainey Harper College, 1994. 53-55.

Mary had said she would put a brass plaque on the headstone to mark Mike’s grave but all that is here is the cold marble and stray pieces of thatch.

Catlin, Bob. "Remembering." The Harper Anthology. Palatine: William Rainey Harper College, 1994. 8-11.