I've been meaning to post something about my experiences with passing the C2 exam for a while, so this is a good prompt. My language journey is maybe a bit unusual, I brushed up an old German GCSE before I moved to Switzerland and managed to pass the B1 course before I made the move but once here I didn't have a strong desire to do a further course for about another 6 years! What prompted me to study further was a realization that when I had stagnated a bit and was making the same old mistakes. I was also weighing up some further education (retraining as a teacher) and that also required the C2. In the end I decided to plump for a private lesson (1.5hours per week at Sprachwelten in Zurich) and it took about 12 months before I felt ready to have a stab at the exam. As with all language exams it's pretty formulaic so you really need to have the exam technique nailed, particularly as certain parts of the exam are pretty tight time wise. You also really need to have the broad range of vocab and doing a course forces you to think about using alternative adjectives and phrases (rather than your stock ones).
So what has the C2 brought me? I think it's been a bit of a confidence boost to be honest because it was challenging and I managed to come through it. It has also been a platform to explore new career opportunities (as I'd been working primarily in English). Ultimately, having the goal of the exam also helped focus my learning on areas of weakness (for mewritten German and Grammar).
Anyway best of luck if you do decide to go for it.
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