The purpose of this research is to analyse the pragmatic development of language groups at different proficiency levels and to investigate the relationship between interlanguage pragmatics and grammatical competence. For this study, 36 native Spanish speaking EFL learners at different proficiency levels were asked to respond in English to 24 different situations that called for the speech acts of request and apology. Results showed three important aspects. The first finding suggested that basic adult learners possess a pragmatic knowledge in their L1 that allows them to focus on the intended meaning and, in most cases, to assemble an utterance that conveys a pragmatic intention and satisfies the communicative demands of a social situation. The second finding revealed that there are two essential conditions to communicate a linguistic action: the knowledge of the relevant linguistic rules and the knowledge of how to use them appropriately and effectively in a specific context. The findings further suggested that advanced learners possess the grammatical knowledge to produce an illocutionary act, but they need to learn the specific L2 pragmatic conventions that enable them to know when to use these grammatical forms and under which circumstances.