A coordinating conjunction is used to join together words, phrases, clauses, or sentences. There are seven coordinating conjunctions: and, but, for, nor, or, so, and yet. These words can be remembered by remembering FANBOYS (F = for; A = and; and so on). The most commonly used of these conjunctions are and and but. And connects similar ideas while but connects two contrasting ones. Although coordinating conjunctions share the basic function of connecting words, phrases, and clauses in a sentence, each of them has a specific meaning. The following show examples of the coordinating conjunctions being used.
For: We use for to express a reason or purpose. It has similar meaning as because, since and as, and can be used in place of any one of them.
And: We use and to add one thing to another.
Nor: We usually use nor before the second negative after the first one. We can also use it as the last of a set of negatives.
But: We use but to introduce an additional phrase or clause that is different from what has already been mentioned.
Or: We use or to show alternatives or different possibilities.
Yet: We use yet to add something surprising because of what has just been mentioned.
So: We use so to mean for this reason. It has similar meaning as therefore.
Avoid repeating unnecessary words when using conjunctions
(For meaning and use of coordinating conjunctions, see List 12 - Conjunctions)