Coordinating Conjunctions: for, and, nor, but, or, yet, so

1. Lucy didn’t like the way the contest was run. She let the judges know it.
2. Lucy didn't like the way the contest was run, and she let the judges know it.

The second example is a compound sentence—two independent clauses joined by
coordinating conjunction.

Punctuation Rule:: Use a comma before a coordinating conjunction when it joins two independent clauses.

Subordinating Conjunctions: as, after, although, because, before, if, when, while,
since, until, unless, so (that), whether, even though

1. The contest was unfair. Many people did not applaud for the winner.
2. Because the contest was unfair, many people did not applaud for the winner.
3. The winner could not enjoy her victory because she knew the contest was
unfair.

The last two examples are complex sentences--one independent clause and one
dependent clause. The dependent clause starts with a subordinating conjunction.

Punctuation Rule: When a dependent (incomplete) clause begins a sentence, use
a comma at the end of the clause. When the independent (complete) clause begins
the sentence, a comma is not necessary before the conjunction.

Adverbial Conjunctions: consequently, furthermore, however, in fact, indeed,
likewise, moreover, otherwise, therefore

1. Everyone wants a new set of rules. Changes are not possible until next year.
2. Everyone wants a new set of rules; however, changes are not possible until
next year.

The second example is a compound sentence—two independent clauses

Punctuation Rule:: Use a semicolon between the independent clauses and a
comma after the conjunction.

Transition Words: Adverbial conjunctions can be used as transition words, but so can many other words.

Examples are simple sentences—one independent clause each.

1. Everyone wants a new set of rules. However, changes are not possible until
next year.
2. Everyone wants a new set of rules. Changes are not possible, however, until
next year.
3. Everyone wants a new set of rules. Changes are not possible until next year,
however.

Punctuation Rule:: Punctuate the sentences and then set off the transition words with commas.