“…Both of these developments reflect the introduction of unbound inflection into the language, that is, an element that carries Tense, Agreement or Mood information or features and that does not form a morphological unit with the verb, being thus not 'bound' to the latter. By the late ME period, do appears to have been used as an aspectual element, marking perfect (Denison 1985) and/or habitual (Garrett 1998) aspect. However, its earlier uses in ME are 'contentful', unlike the modem semantically empty element.…”