:: : An assertion that " German is more agglutinating than English " is quite dubious, since very little of the additional inflectional morphology that German has with respect to English could be accurately called " agglutinating ", while much of the difference between English and German in compounding actually has a lot more to do with orthographic conventions ( adding more word spaces in writing vs . running words together in writing ) than with deep-seated linguistic structure differences.
42.
This clearly suggests that the tense / aspect categories originated as separate lexical verbs, part of a system of derivational morphology ( compare the related verbs " to rise " and " to raise ", or the abstract nouns " produce ", " product ", " production " derived from the verb " to produce " ), and only gradually became integrated into a coherent system of inflectional morphology, which was still incomplete at the time of the proto-language.
43.
Note that most modern Germanic languages have lost most of the inherited inflectional morphology as a result of the steady attrition of unstressed endings triggered by the strong initial stress . ( Contrast, for example, the Balto-Slavic languages, which have largely kept the Indo-European pitch accent and consequently preserved much of the inherited morphology . ) Icelandic and modern German best preserve the Proto Germanic inflectional system, with four noun cases, three genders, and well-marked verbs.
44.
:: I don't know, but probably the most easily-definable concrete interpretation of " active in common usage " ( i . e . participating in root-and-pattern inflectional morphology ) would be slightly different for Arabic and Hebrew, since in Arabic broken plurals would count, while in Hebrew only verbs would count ( Hebrew does have historical remnants of broken plural formations in one particular case, but it's hard to say that this is synchronically-productive root-and-pattern morphology, especially in modern Hebrew ).
