In this field study report, the author investigates behaviour associated with inviting in order to see if there is any effect on the language used across cultures due to factors such as status, age, gender in actual social interactions. Chapter one gives a brief introduction to the important role of the English Language in the world in general, and in Vietnam nowadays in particular, and a review of Teaching Methods which have been used in Vietnam so far. Chapter two will deal with the theoretical background, language competences including linguistic competence, sociolinguistic competence and communicative competence. In addition, speech act theory , face work, distance, power in relation to status, age and gender as well as reviews research on the differences between spoken and written are also discussed. Chapter three defines the structure of an invite with its social and cultural characteristics focussing on the natural structure of a spoken invitation. Chapter four describes research and data analysis of the issuing, accepting and declining of spoken invitations used by Vietnamese speakers of Vietnamese (VSV). Chapter five contains the data analysis of the issuing, accepting and declining of spoken invitations used by Australian speakers of English (ASE). Chapter six discusses the comparison of Vietnamese and Australian spoken invitations, the main difference being found in the use of much more direct forms used in VSV as opposed to more tentative forms preferred by ASEs. Directness of form, however, does not reflect a lack of politeness, which is conveyed to a much larger extent by other prosodic and paralinguistic features. Chapter seven is a brief cross-cultural investigation of the spoken invitations of Vietnamese learners speaking English. This shows up a degree of cross-cultural interference and offers some implications for the classroom. Chapter eight contains a summary and conclusion. The results of the study may suggest that Vietnamese learners of English need to be taught not only linguistic competence but also communicative competence with an emphasis on cultural and social factors. Spoken invitations which really have some function in actual interactions need to be incorporated in the program for teaching spoken English.