Home viral 500 Days of Duolingo: What You Can (and Can’t) Learn From a Language App 500 Days of Duolingo: What You Can (and Can’t) Learn From a Language App Author - Upworthy May 04, 2019 0 By ERIC RAVENSCRAFT from NYT Smarter Living https://nyti.ms/2vAKCjT Tags Hot NEWSNEWSNYTTodaytodaysviral Facebook Twitter Whatsapp Newer Older