This article explores the lexico-semantic network through a brief examination of the English preposition \'in\' and its equivalent \'trong\' in Vietnamese. Working within a cognitive linguistic framework, the investigation presents the six clusters of senses of the preposition \'in\' based on Tyler and Evans’ research, thereby, via the contrastive analysis approach, indicating the similarities and differences in the way speakers of the two languages conceptualize the world via their spatial configuration. The differences result from the cultural features of Vietnamese in their early settlement custom which have shaped their distinctive cultural habits. The major reason lies in the formation of cognitive mappings of the Vietnamese. As a result, it is necessary for foreign learners of Vietnamese or Vietnamese learners of English to master cognitive mappings of both languages. Finally, the article puts forward some suggestions to provide an overview for translators/interpreters to avoid possible mistakes in translating spacial language, specifically the English preposition “in” and the Vietnamese “trong”.