Got it. The system does use a state-of-the-art POS tagger, but I think 'key' was mistakenly tagged as an adjective instead of as a noun for your sentence. I'll

Got it. The system does use a state-of-the-art POS tagger, but I think 'key' was mistakenly tagged as an adjective instead of as a noun for your sentence. I'll try to fix that -- thank for pointing it out!