This study examines whether a Pedagogical Translanguaging (PTL) teaching approachoutperforms a Monolingual (ML) approach in a laboratory setting. While classroom-basedresearch on PTL suggests it may be more effective, such findings are hard to generalise. Here,147 adult Francophones learned a pseudo-language across two within-subject conditions: PTLversus ML, and Cognate versus Novel suffixes. Participants completed five training exercisesand were tested on Lexical comprehension (LC) and Morphological comprehension (MC) bothimmediately and after a one-week delay. Multilingualism and analogical reasoning wereincluded as fixed effects. Results showed ML outperformed PTL in LC, with no effect in MC,suggesting laboratory settings may not capture PTL's classroom advantages or that a moreintegrative method is needed. Cognate suffixes aided LC but not MC, aligning partially withCognate superiority literature. No main effect of Multilingualism was found, thoughexploratory analysis indicated greater language repertoire enhanced ML's LC outcomes.Analogical reasoning was significant overall. MC was harder than LC, but MC improved afterdelay, while LC was better immediately, highlighting distinctions between item-based andrule-based learning.