“…In order to see the challenges this learning scenario potentially poses for the learner in the absence of access to a domain-specific knowledge about the structural possibilities natural languages offer, consider the following: On the surface, it looks like Mongolian is a Trochaic and Weight-Sensitive language, but a strange one in that End-Rule, the parameter that determines the location of main stress, appears to be sometimes set to Left (2a, b), sometimes to Right (3a, b, d), and sometimes even to Middle (2c, d, f), and sometimes replaced by Leftmost-Wins (4c), a system that is linguistically impossible [more on this in (7) and (8) below], and crucially one that is, thus, ruled out by UG. If, however, these systems are considered to be prominence-driven, and independent of foot structure ( Walker, 1997 ), or if the default (left edge) ‘stress’ at least were to be considered ‘intonational prominence’ instead of stress (e.g., Gordon, 2000 ; Özçelik, 2017 ), such systems would find a more viable explanation, especially since the Foot is no longer considered to be a universal, i.e., not every prosodic word needs to be headed by at least one foot (e.g., Özçelik, 2011 , 2014 , 2017 ; Garcia and Goad, 2021 ).…”