The theme of this research is the execution of the acts of asking, registered in unofficial signs and posters, located in public circulation spaces of the Brazilian society. From an interdisciplinary perspective, this study aims to contribute to a better understanding of the identity and cultural issues brought in and by the language, providing relevant subsidies for the teaching of Portuguese as a Second Language for Foreigners (PL2E). Although signs and posters aim to keep the necessary information clear to the reader and active in memory, not always the main content conveyed is explicit in the utterance and is often constructed by means of implied information. For learners of PL2E, understanding this unsaid message, especially in statements expressed by unofficial placard and poster warnings, requires not only a major challenge, but can also generate misinterpretations and distorted views of the target culture. With this in mind, the ways in which discursive strategies regarding the act of asking are realized are described and analyzed, trying to verify to what extent the contextual and cultural factors influence the choice of the linguistic strategies used to elaborate explicit or implicit acts of asking. To this end, the theoretical foundation of this dissertation is based on the concepts of Speech Acts Theory, Interactional Sociolinguistics, Interculturalism and Social Anthropology.