“English Only.” It’s 2008 in Karaj, Iran and four adult students are studying for the Test of English as a Foreign Language, the key to their green card, medical school, family reunification. Playing out in awkward lessons of word games and mistranslation, English is both a comedy of miscommunication and a look at the ways speaking a new language can expand your world and change your voice. A hit in its 2021 New York premiere, Studio presents playwright Sanaz Toossi in her Washington, DC debut.