Conjunctions are the words we use to link two (or more) words, phrases, clauses, or sentences.
Coordinating
The most well-known conjunction, these connect two elements that are considered equal parts of a sentence. The mnemonic device FANBOYS can help you remember them:
For (reason or explanation)
And (additional item or idea)
Nor (additional item or idea)
But (contrast or exception)
Or (alternative item or idea)
Yet (contrast or exception)
So (consequence)
NB: the words FOR, YET, and SO can also act as other parts of speech.
Why does it matter?
Some teachers, editors, and style guides maintain the rule of not beginning a sentence with a coordinating conjunction.
Subordinating
These conjunctions join a subordinate (dependent) clause to a main (independent) clause. Examples include although, as, because, before, even though, since, so, unless, etc.
NB: many of these conjunctions can also function as other parts of speech.
Why does it matter?
Subordinating conjunctions help vary sentence length and structure, which may be the best tool a writer can use.
Correlative
Like coordinating conjunctions, these word pairs join two equal parts of a sentence, for example: either/or; neither/nor; not only/but (also); rather/than; etc.
Why does it matter?
With correlative conjunctions, everything must be equal. A sentence like “Sasha both walked to the store, and Stacy ran a race” doesn’t work. Since the conjunction “both” is placed after the subject “Sasha” she has to be the subject of both verbs.
Any questions?
Read more of my Grammar Guide.