Learning a foreign language involves far more than simply learning its linguistic system. To be able to communicate successfully in a foreign language, learners need, among other things, a degree of acculturation. This means that they need to familiarize themselves with certain sociolinguistic norms surrounding language use. Failure to consider such sociolinguistic factors might result in a breakdown in communication despite the use of accurate language forms. At the same time, gratitude and suggestion speech acts are among the frequently needed functions of language. The aim of the present book is to examine the learning of these speech acts by Iranian EFL learners. Apart from a theoretical review of the recent research on these two speech acts, this book also contains an empirical analysis of the effects of three classroom presentation techniques (task-based, cross-linguistic comparison and implicit) on EFL learners' short and long term comprehension and production of gratitude and suggestion speech acts. This book may be helpful not only for language teachers and learners but also for the experts and students of sociolinguistics.