In grammar, a conjunction is a part of speech that connects two words, sentences, phrases or clauses together. A discourse connective is a conjunction joining sentences. This definition may overlap with that of other parts of speech, so what constitutes a "conjunction" must be defined for each language. In general, a conjunction is an invariable grammatical particle, and it may or may not stand between the items it conjoins.
The definition can also be extended to idiomatic phrases that behave as a unit with the same function as a single-word conjunction.
Many students are taught that certain conjunctions (such as "and", "but", and "so") should not begin sentences, although this belief has "no historical or grammatical foundation".
Coordinating Conjunctions
Coordinating conjunctions, also called coordinators, are conjunctions that join two or more items of equal syntactic importance, such as words, main clauses, or sentences.
Can be used to remember the coordinators for, and, nor, but, or, yet, and so. These are not the only coordinating conjunctions; various others are used, including: ch,"and nor”, "but nor", "or nor”, "neither" ("They don't gamble; neither do they smoke"), "no more" ("They don't gamble; no more do they smoke"), and "only" ("I would go; only I don't have time").
Examples:
For: presents a reason ("He is gambling with his health, for he has been smoking far too long.") (Though "for" is more commonly used as a preposition)
And: presents non-contrasting item(s) or idea(s) ("They gamble, and they smoke").
Nor: presents a non-contrasting negative idea ("They do not gamble, nor do they smoke.")
But: presents a contrast or exception ("They gamble, but they don't smoke.")
Or: presents an alternative item or idea ("Every day, they gamble or they smoke.")
Yet: presents a contrast or exception ("They gamble, yet they don't smoke.")
So: presents a consequence ("He gambled well last night, so he smoked a cigar to celebrate.")
When a coordinating conjunction connects two independent clauses, it is often (but not always) accompanied by a comma.
When a coordinating conjunction is used to connect all the elements in a series, a comma is not used:
ü Presbyterians and Methodists and Baptists are the prevalent Protestant congregations in Oklahoma.
A comma is also used with but when expressing a contrast:
ü This is a useful rule, but difficult to remember.
In most of their other roles as joiners (other than joining independent clauses, that is), coordinating conjunctions can join two sentence elements without the help of a comma.
Correlative Conjunctions
Correlative conjunctions are pairs of words that are used to link words together. The most important thing to remember when using correlative conjunctions is that the words, phrases, or clauses that are put together must be the same type. That means that nouns must be put together with other nouns, verbs with other verbs, adjectives with other adjectives, and so on. This point will be more fully explained following the list of frequently used correlative conjunctions.
Correlative conjunctions are pairs of conjunctions that work together to coordinate two items. English examples include both…and, [n]either… [n]or, and not [only]…but [also], whether... or.
Examples:
Either do your work or prepare for a trip to the office.
Not only is he handsome but he is also brilliant.
Neither the basketball team nor the football team is doing well.
Both the cross country team and the swimming team are doing well.
Whether you stay or go is your decision.
Either do your work or prepare for a trip to the office.
Not only is he handsome but he is also brilliant.
Neither the basketball team nor the football team is doing well.
Both the cross country team and the swimming team are doing well.
Whether you stay or go is your decision.
When you use correlative conjunctions, be careful about verb agreement.
If you connect two subjects with a correlative conjunction, the second one must agree with the verb that follows.
Every single evening either the horned owl or the squabbling cats wake Samantha with their racket.
Every single evening either the squabbling cats or the horned owl wakes Samantha with its racket.
When you use correlative conjunctions, be careful about pronoun agreement.
If you connect two antecedents with a correlative conjunction, the second one must agree with the pronoun that follows.
Neither Yolanda nor the cousins expressed their disappointment when blind Aunt Sophie set down the plate of burnt hamburgers.
Neither the cousins nor Yolanda expressed her disappointment when blind Aunt
Sophie set down the plate of burnt hamburgers.
When you use correlative conjunctions, be careful about parallel structure.
Either ... or, neither ... nor, and not only ... but also require special attention when you are proofreading for parallelism. Be sure that you have equal grammatical units after both parts of the conjunction. You can have two main clauses like this:
Not only did Michael grill a steak for Tiffany, but he also prepared a hotdog for Rocket, her dog.
Subordinating Conjunctions
Subordinating conjunctions, also called subordinators, are conjunctions that introduce a dependent clause. The most common subordinating conjunctions in the English language include the following: after, although, as if, as much as, as long as, as soon as, as though, because, before, but, even if, even though, if, in that, in order that, lest, since, so that, then, that, though, unless, until, when, whenever, where, wherever, whether, and while.
Complementizers can be considered to be special subordinating conjunctions that introduce complement clauses (e.g., "I wonder whether he'll be late. I hope that he'll be on time"). Some subordinating conjunctions (until, while), when used to introduce a phrase instead of a full clause, become prepositions with identical meanings.
In many verb-final languages, subordinate clauses must precede the main clause on which they depend. The equivalents to the subordinating conjunctions of non-verb-final languages such as English are either.
The form of the verb used is formally nominalised and cannot occur in an independent clause.
The clause-final conjunction or suffix attached to the verb is actually formally a marker of case and is also used on nouns to indicate certain functions. In this sense, the subordinate clauses of these languages have much in common with postpositional phrases. Coordinating conjunction has normal word order, but the clause after the subordinating conjunction has verb-final word order.
A Subordinating Conjunction (sometimes called a dependent word or subordinator) comes at the beginning of a Subordinate (or Dependent) Clause and establishes the relationship between the dependent clause and the rest of the sentence. It also turns the clause into something that depends on the rest of the sentence for its meaning.
ü He took to the stage as though he had been preparing for this moment all his life.
ü Because he loved acting, he refused to give up his dream of being in the movies.
ü Unless we act now, all is lost.
Notice that some of the subordinating conjunctions in the table below after, before, since are also prepositions, but as subordinators they are being used to introduce a clause and to subordinate the following clause to the independent element in the sentence.
An adverb clause is always introduced by a subordinating conjunction. A noun clause and adjective clause sometimes are.
Adverb clause: Before you go, sign the log book.
Noun clause: He asked if he could leave early.
Adjective clause: That is the place where he was last seen.
A subordinating conjunction is always followed by a clause. Many subordinating conjunctions can be other parts of speech.
Adverb: Jill came tumbling after.
