The evolution of aspectual composite wesan + Participle I / Infinitive in written records of the XIII - XVIth centuries

Durative composite wesan + Participle I / Infinitive existed in definite period of German language history, had a potential possibility to be included to the tense system of German, and then came out of the use. The aim of this publication is the determination of language internal facts, which determine the disappearance of durative composite wesan + Participle I / Infinitive by the beginning of the New High German.