My apologies for having overlooked the above posting of yours. I saw it only today when I went through the previous postings in this discussion board.
Yes, there are indeed seven coordinating conjunctions in English, and for easy recall, they are usually sequenced such that their first letters mnemonically form the acronym
“fanboys”:
for,
and,
nor,
but,
or,
yet, and
so. By definition, a coordinating conjunction is a function word that connects two or more word groups of equal grammatical rank; typically, it links independent clauses to form compound sentences, or links parallel sentence elements. (For details about its usage, check out
“Lesson #6 - The Six Basic Logical Relationships in Language” in the Forum.)
There really is no such thing as “pure conjunctions” in English; in the case of the coordinating conjunctions “yet” and “so” in particular, it just so happens that the words that stand for them also function as other parts of speech depending on how they are used.
Yet. The word “yet,” which is a coordinating conjunction that means “but” or “but nevertheless,” also doubles up as an adverb in several senses. It means “in addition” in the sentence “The stern judge sentenced the prisoner
yet another year of imprisonment for bad behavior”; “up to now” or “so far” in “She hasn’t delivered
yet on her promise to us”; and “however” in “They have as
yet found no solid proof that he stole government funds.” In the particular sentence that you provided, “She said she would be late,
yet she arrived on time,” the word “yet” definitely functions as a coordinating conjunction in the sense of “but nevertheless.”
So. In the case of “so,” which is a coordinating conjunction that means “with the result that,” in order that,” or “for that reason,” also works as an adverb, adjective, and pronoun. It works as an adverb in the sense of “in a manner or way indicated or suggested” in the sentence “They were convinced that he was dishonest and they said
so to their manager”; and in the sense of “to an indicated or suggested extent or degree” in “She has never been
so lucky in her entire career.” Second, it works as an adjective in the sense of “conforming with actual facts” in the sentence “The accused gave testimony that just was not
so” or in the sense of “marked by a desired order” in “He wanted his car to be parked in the garage just
so.” And third, it works as a pronoun in the sense of “such as has been specified or suggested” in the sentence “If you have to leave, do
so right now.”
As I’m sure you’ve already discovered, the great majority of English words have multiple meanings, senses, and usages. English dictionaries are so thick because of this. This is a clear measure of how rich the English lexicon is and this requires learners of English to get to learn more and more of those various meanings, senses, and usages to truly achieve mastery of the language.