Conjunctions join words, phrases, or clauses. The three different types of conjunctions indicate different relationships between the elements joined. Coordinating conjunctions link elements of equal value. Correlative conjunctions are used in pairs to establish a specific relationship between elements of equal value. Subordinating conjunctions indicate that one element is of lesser value (subordinate) to another element.
1. Use a coordinating conjunction to connect elements (words, phrases, or clauses) of equal grammatical value.
and, but, or, nor, for, so, yet
(Note: These are often remembered with the acronym FANBOYS.)
Swimming and reading are my two favorite summer activities. (Swimming and reading are both subjects in the sentence.)
Please place the papers on top of the desk or in the drawer. (On top of the desk and in the drawer are both prepositional phrases.)
She wanted to drive the car, but she had never received her license. (She wanted to drive the car and she had never received her license are both independent clauses.)
2. Use correlative conjunctions in pairs to connect words, phrases, or clauses of equal grammatical value. Correct use of these conjunctions is critical in achieving parallelism in sentence structure (see TIP Sheet on "Achieving Parallelism").
not only...but also
You must decide either to fly or to drive. (The elements to fly and to drive are both infinitives.)
Contrary to my plans, I spent much of my vacation both correcting papers and contacting students. (The elements correcting papers and contacting students are both participial phrases.)
I hope not only that you will attend the play, but also that you will stay for the cast party afterwards. (The elements that you will attend the play and that you will stay for the cast party afterwards are both subordinate clauses.)
3. Use a subordinating conjunction to connect a subordinate (dependent) clause to an independent clause.
after even though than whenever although if that where as in order that though whereas as if rather than unless wherever because since until whether before so that when while
(Note: Some of the words listed can serve as different parts of speech, depending on how they are used.)
If you finish your homework, you will be prepared for the test. (If you finish your homework by itself is an incomplete thought.)
I lose myself in the music whenever I practice the piano. (Whenever I practice the piano by itself is an incomplete thought.)
4. Conjunctive adverbs (sometimes called adverbial conjunctions) are used to indicate a relationship between sentences and independent clauses.
however therefore moreover nevertheless
Carrot cake is very tasty. Moreover, the carrots make it a "healthy" choice for dessert.
I realize you were busy. It is unfortunate, however, that you missed that phone call.
The hurricane has lessened in intensity; nevertheless, we are evacuating in an hour.