Corrigible literally means correctable, while incorrigible literally means uncorrectable. From this, you might conclude that the two words are opposites.
However, most speakers don't think of incorrigible as defined in terms of corrigible. In fact, I would venture to guess that many speakers aren't familiar with the word corrigible at all! The two words have their own idiomatic patterns of usage, and they don't correspond in manner or frequency.
If you did say corrigible flirt, I think it would be interpreted in one of two ways:
- unidiomatic or incomprehensible; or
- wordplay, coining the word anew as a back-formation from incorrigible.
This sort of wordplay happens all the time, as when people re-invent the word gruntled (from disgruntled). It works because gruntled is an obsolete English word few people are familiar with. Likewise, corrigible is relatively unknown, and though it's not quite obsolete, it isn't generally used in this fashion. Because of this, I'd expect corrigible flirt to be interpreted as either novel or mistaken.
What great examples!
As for the last set of sentences: I'd call them just about interchangeable, except that "a lot" would be regarded as less formal. (NOAD tags "a lot" as "informal," e.g.) If I was proofreading my own writing, I'd probably change "I don't know a lot about" to "I don't know much about." Either would be fine in conversation, though.
I don't know much about Western history. {okay}
I don't know a lot about Western history. {okay in conversation, perhaps a bit informal for writing}
As for the middle set: I'd rephrase the latter sentence to read, "I don't watch a lot of TV." The first one could also be rephrased ("I don't watch very much TV"), but those two sentences have slightly different meanings: "I don't watch TV very much" would probably be interpreted as "I don't watch TV very often"; while "I don't watch very much TV" sounds more like "I don't watch many TV programs". The difference is very subtle, but I think it's existent. If I watched a half hour of TV nightly, but always the same program, I'd be inclined to say, "I don't watch a lot of TV," but not, "I don't watch TV very much." (After all, I watch nightly!)
I don't watch TV very much. {you don't watch TV very often}
I don't watch a lot of TV. {you don't watch too many TV programs}
I don't watch TV a lot. {not wrong per se, but I'd recommed one of the others}
As for the first set, that latter sentence sounds off to me. Interestingly enough, I have no problem with its inverse: "I like Japanese food a lot." However, when speaking in the negative, "I don't like Japanese food very much" sounds much more polished than "I don't like .. a lot."
I don't like Japanese food very much.
I don't like Japanese food a lot. {use the first one, not this one}
I like Japanese food very much.
I like Japanese food a lot. {in the positive, you can use either one}
I'm marveling how, even though the three pairs of examples all have the same sentence structure, my comments are different for all three. I guess this is a trickier problem than one might first expect.
Best Answer
A conjunction at the beginning of a sentence is perfectly grammatical for most contemporary readers, although it was deprecated by several generations of schoolmarmish stylists. You're perfectly safe using and, but or or there. Keep in mind, however, that they are conjunctions, not adverbs, and should not be separated from the clause they introduce with a comma, unless that comma is the first bracketing a parenthetical remark.
Plus, however, is another matter. Use of plus in any but the mathematical sense is distinctly colloquial. It may be employed as a conjunction in the chattier sort of business or technical writing, but this should be avoided in academic contexts.