1. Commas & Semicolons

2. Commas
Commas help the reader figure out which words go together in a sentence and which parts of your sentences are most important. Using commas incorrectly may confuse the reader, signal ignorance of writing rules, or indicate carelessness.

3. Use a comma before a coordinating conjunction that joins independent clauses (unless the independent clauses are very short):
I wrapped the fresh fish in three layers of newspaper, but my van still smelled like trout for the next week. (commas with two independent clauses)
Use a comma after an introductory adverb clause and, often, after an introductory phrase (unless the phrase is very short):
After the hospital had completed its fund-raising campaign, an anonymous donor contributed an additional $10,000.
(after introductory adverb clause)

4. Commas are always used to set off certain adverbs at the beginning of a sentence, including however, in fact, therefore, nevertheless, moreover, furthermore, and still. 1. Therefore, a comma would be appropriate in this sentence. 2. In fact, I will use one.

5. Two independent clauses MUST be joined by a comma before a coordinating conjunction (for, and, nor, but, or, yet, so) to avoid a run-on sentence . In the following sentences, where the second clause is independent (because it can stand alone as a sentence), the comma is necessary: 1. Mary walked to the party, but she was unable to walk home. 2. Designer clothes are silly, and I can't afford them anyway.

6. Semicolon;
A semicolon is use to combine two independent clauses when they both refer to the same idea.
Call me tomorrow; I will give you my answers.
Also merge two independent clauses when the second one starts with a conjunctive adverb or transition.
I have paid me dues; therefore, I expect all the privileges listed in the contract.
Use a semicolon to separate a series.
This conference has people who have come from Boise, Idaho; Los Angeles, California; and Nashville, Tennessee.

7. Comma Game