The study examines how three undergraduate beginner students of Italian as L3 make sense of Italian tense-aspect morphology based on other languages. All students had knowledge of Swedish, English, and French, in each case acquired in a particular chronological order. The participants completed two C-tests and three interpretation tests of aspectual contrasts in English, French, and Italian. The latter was complemented by written comments. The results of the Italian interpretation test varied depending on tense-aspect configurations. A qualitative analysis of the comments revealed four categories of metalinguistic reflections, referring to: (i) explicit rules, (ii) intuition, (iii) other languages, and (iv) uncertain/unknown, differently distributed among the students. The results suggest that the students relied on their L1(s) as well as their L2(s) depending on type of transfer, whether linguistic or conceptual, which is discussed in light of some recent L3 models.