The purpose of this research was to explore the relationships between design, learning, and translanguaging in a 3D collaborative virtual learning environment for adolescent learners of Chinese and English. We designed an open-ended space congruent with ecological and dialogical perspectives on second language acquisition. In such a space, sense-making is contingent on the relational dynamics of place, activities, and artefacts. These spaces encourage meaning-making in situ, manipulation of virtual objects within places, and coordination among players. Our investigation looked at how learners of Chinese and English collaborated on a project in which they decorated a virtual living room. The findings suggest that socioculturally bounded places afford unique learning opportunities. Firstly, learning occurred through "referencing", which is the mutual clarification of a virtual object's meaning, position, and function, in relatively stabilised places, such as a museum, and secondly, learning occurred through coordination between verbal instruction and object manipulation in more adaptive places, which we call eco-dialogical learning. We also found a strong relationship between translanguaging and object manipulation. We conclude the paper from the perspective of how the eco-dialogical model resulted in designs that promoted cognition and interactivity.