Work, as a noun, is collective. You have difficult work. But that wouldn't be a correct translation for this sentence because yrke = profession. Unlike work, a profession generally requires training and formal qualifications.
My best suggestion is to separate the syllables and take them on one at the time, yr-ke. The Norwegian Y is a difficult one, but it is very close to our I. Say "eee" (the Norwegian "I") and push your lips out in a donut and you'll hear the sound change.