What are the fanboys words
FANBOYS stands for for, and, nor, but, or, yet, and so. These are commonly taught as the seven coordinating conjunctions in English. They can connect elements of equal grammatical status, including words, phrases, and independent clauses.
Meaning and context
The mnemonic helps you remember the words, but correct punctuation depends on what they connect. When a coordinating conjunction joins two independent clauses, a comma commonly comes before it. A simple pair of words usually does not require that same comma pattern.
Examples and usage
We stayed inside, but the rain stopped later joins two complete clauses. Tea or coffee joins alternatives. The original example She packed slowly, yet she arrived early uses yet to introduce a contrast. Check that both sides can stand alone before applying the independent-clause rule.

What to check
Do not place a comma before every occurrence of a FANBOYS word automatically. Also distinguish a coordinating use from another grammatical use of the same word. Read the whole sentence and identify the units being joined.
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