1. Promovieren - This refers only to the obtaining of a doctor's degree, i.e. die ('Doktorwürde') or the act of giving someone the Doctor's degree. e.g. Ich habe promoviert, or: Ich wurde von der Fakultät X zum Doktor promoviert. 2. Graduieren - the act of giving someone an academic qualification (upon completion of a course) or the act of completing an academc qualification. This word mainly refers to tertiary study levels...you wouldn't really use it for a high school setting. 3. Absolvieren - i) completing an academic course or school. This can refer to any type of school or course. E.g. einen Lehrgang absolvieren, das Gymnasium absolvieren ii) absolvieren can also be used to say that you passed an exam: Hat er sein Examen absolviert? iii) absolvieren can also be used in a non-academic context, meaning 'to manage', 'to tackle' something, e.g. Er muss einen Achtstundentag absolvieren; ein hartes Training absolvieren