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How many of the 170k English words do you know?
Fascinating! As a native speaker, I got 89/100 ("you know 72,000 words"), but perfect on the core and intermediate levels. There were a few that I knew I'd heard before, but couldn't quite place, and then there were some words that I just got lucky with my experiences, like having recently reread Gulliver's Travels and being asked about "brobdingnagian," which literally comes from that book.
I'm curious what other native speakers get, and how difficult even the lower levels are for those learning English.