Translation:Matěj is bad, but František is different.
I don't doubt that you learned such a rule; I probably did, too, and just don't recall learning it, since I've been speaking English since forever. But this discussion is interesting.
Neither the Cambridge Dictionary (UK) nor the Merriam-Webster Dictionary (US) offers a definition of "however" as a conjunction meaning "but."
And that surprised me, because I have heard it quite often (mainly in the US) used in this way -- by which I mean NOT in the semi-colon-separation-of-clauses way, but as a substitute for the simple "but." But (However,) I wouldn't argue with the dictionaries.
So I have a question. If the Czech sentence were written with a semi-colon, would "however" be acceptable? Or is the semi-colon used differently in Czech? Thanks!
The semi-colon is used pretty rarely in Czech but I can't comment too much about English.
For : "However, František is different." or "František is, however, different." I would use just "František je [ale/ovšem] jiný." in Czech.
"Ale František je jiný." is possible, but in this case I would rather connect that to the preceding clause into a compound sentence. As a stand-alone sentence it can be an answer to someone ("But František is different!").
Hmm...I'm doing some research on this grammatical point, as I know I've seen it used as such....Certain resources claim it's fine, though a semicolon seems the prefered seperator preceding the second clause and conjunctive adverb "however"; whereas other resources say, this at best a literary faux pas. Do you have a good reference source? Thanks for your time!
I'm not sure about the validity of this source or the content within, but I did find this short resource on quora, insightful and generally more explanatory to commonly accepted usage distinctions between "but" and "however". https://www.quora.com/Diction-and-Word-Usage-What-is-the-difference-between-but-and-however