This lesson took place in a SSN course designed for a group of B1 level premed students from the University of Virginia. It consists of several «input processing» tasks which focus on «se» form; a pronoun which is as confusing for the average student as frequent in the field of Health («se toma la temperatura, se opera, se hace un esguince, se resfría», etc.) The aim is to engage students in a thought process on the «se» structure, its meanings and usage («se active agent vs passive recipient» and «accident vs process») through several tasks of interpretation. Each is divided into four sections of fifteen minutes. Not only does the lesson have a high degree of personalization, but it also encompasses linguistic (speaking and writing) and transversal competencies, (autonomy and cooperation) with primary focus on the cognitive ones (awareness and processing). Key words: awareness, input processing, form and meaning, «se».