Firstly, there should be a -p at the end of the pronunciation.
Secondly, sk- is pronounced like in the recording when it comes before the vowels e, i, y, ä, ö in most cases. This is because of historical reasons. Those vowels are pronounced in the front of the mouth so the consonants that came before these vowels were gradually moved forward until they became ”soft”.
Therefore we now have a series of consonants that are pronounced with this ”hw”-sound (in Swedish called the sje-sound). These clusters are e.g. sj, sk, skj, stj. It is known for having many other spellings, especially in loanwords like ”choklad” and ”genre” and words on -tion like ”station”.
The same thing happens to ”k” which is pronounced ”sh” in front of e, i, y, ä, ö and ”g” which is ”y” in front of the same vowels.
It should not have a clear f-sound.
It should be pronounced roughly like the German ach-laut in Bach but with rounded lips and with the articulation moved further to the front so it doesn’t have any throat friction. It sounds roughly like when you are blowing out a candle.
You could also describe it as an f-sound but without your upper teeth touching your bottom lip and instead having rounded lips and move the articulation slightly further back.
This seems to be a relatively new behaviour for Duolingo. I'm pretty sure it used to just show the official answer. I guessed "scarves", so it showed me "sashes". Grr. Even if "sash" is a possible meaning for "skärp", I don't think it's helpful.
When I remember to, I just put "x" for a word I don't know instead of guessing, to try to prevent Duolingo from giving me bizarre or misleading "corrections". Double grrrr.
Also sometimes as in this lesson with all the different clothing artikals.. You might think that u r never going to get the hang of it but u do after a while. Also I learned to figure out if a word is an en or ett word from the beginning..i am enjoying the course a lot... Thanks Duolingo...
The main translation is "belts". We also accept "sashes" since that can be a good translation occasionally. However, we don't put it in the hints because we don't think it's important enough for that. Unfortunately, Duolingo doesn't care so it will still show you "sashes" if it thinks that's the closest correct translation to what you enterred.
It's not a rule that covers everything, but it's a very common pattern indeed. There's some more info e.g. here: https://www.lysator.liu.se/language/Languages/Swedish/Grammar.html#nouns
(By the way, you probably know this but it should be barnen - the word barmen means "the bosom".)