combining double acute accent
My keyboard layout gives me pretty easy access to all the Hungarian characters except for ő and ű. For other sorts of diacritical marks, there is a Unicode character called "combining" that you type after another letter, and it adds the diacritic to the letter. These then tend to have a several digit code you enter after hitting the Alt key. For instance the combining (single) acute accent is Alt+0769. I have just looked up that the diacritic for ő and ű is called a double acute accent. I can find the Alt codes for 4 (upper + lower case) letters with the double acute accent attached but haven't for one for the combining character (I want to memorize Hungarian words, not excess numeric codes! ;)
Here are the codes.
We Hungarian can write: ö: AltGr with =, than o ő: AltGR with 0, thank o ü: AltGr with =, then u ű: AltGr with 0, than u
I don´t know that it works with English keyboard.
Here is what I have found: there doesn't appear to be an Alt code for this character.
However, in some applications - Word, yes; Explorer and Firefox, no :( it's possible to enter characters via their Unicode codes.
To enter the combining double acute accent, type the letter you want it over then 030b then Alt+x. On pusing Alt+x the 030b you entered will vanish, replaced by the diacritic over the letter.
So if you get far enough that you're typing Hungarian documents in Word, there you go. For Duolingo, well, I guess that little character menu will do.
Alternately, you can go to character map, search for the character by name, select it, and then paste it were you need it. For whatever reason, if you're pasting it into a browser, it will probably show up 2 or 3 times (well, at least on my computer), you then backspace to get it down to one.
There do appear to be Alt codes for the individual characters: Alt + 0336; Alt + 0337; Alt + 0368; Alt + 0369 But they don't seem to work in my browser, either (probably why they don't show up in Character Map).
If you can type combining acute accent (U+0301) with Alt+0769, then you may be able to get the combining double acute accent (U+030B) with Alt+0779, since that's the decimal version of that combining character's Unicode code point.
I'm not sure whether "o + combining double acute accent" will be accepted by Duolingo in place of the precomposed character, though - but it's worth trying out.