While Ancient Greek is commonly considered a “synthetic” language, I show that it diddevelop periphrastic constructions, to a much larger extent than is generally thought. Iconcentrate on the development of constructions with the verbs ‘HAVE' (εχω) and ‘BE'(ειμι) and a participle, and argue that they underwent a common semantic development,which I propose to call ‘transitivization’. I furthermore draw attention to the importanceof investigating the interrelationship of the different periphrastic constructions underanalysis with regard to their origins, development and decline.