Conjunction (grammar)

 http://en.wikipedia.org/wiki/Conjunction_%28grammar%29
In grammar, a conjunction (abbreviated CONJ or CNJ) is a part of speech that connects two words, sentences, phrases or clauses together. A discourse connective is a conjunction joining sentences.

Many students are taught that certain conjunctions (such as "and", "but", "because", and "so") should not begin sentence

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. In English, the mnemonic acronym FANBOYS can be used to remember the coordinators for, and, nor, but, or, yet, and so.^[2][3] These are not the only coordinating conjunctions; various others are used, including^{[4]:ch. 9[5]:p. 171} "and nor" (British), "but nor" (British), "or nor" (British), "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").
Here are some examples of coordinating conjunctions in English and what they do:

for 

presents a reason ("He is gambling with his health, for he has been smoking far too long.").

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.").

Correlative conjunctions

Correlative conjunctions work in pairs to join words and groups of words of equal weight in a sentence. There are six different pairs of correlative conjunctions:

1. either...or
2. not only...but (also)
3. neither...nor (or increasingly neither...or)
4. both...and
5. whether...or
6. just as...so

Examples:

• You 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 you go, it's your decision.
• Just as many Australians love cricket, so many Canadians love ice hockey.

Subordinating conjunctions

Subordinating conjunctions, also called subordinators, are helpful in writing paragraphs with an independent clause and a dependent clause. The most common subordinating conjunctions in the English language include after, although, as, as far as, as if, as long as, as soon as, as though, because, before, if, in order that, since, so, so that, than, though, unless, until, when, whenever, where, where as, wherever, 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 and while), when used to introduce a phrase instead of a full clause, become prepositions with identical meanings.