Theoretical Grammar The subject-matter of theoretical grammar. Its relation to practical grammar

Class II lost its specific –ode ending due to the levelling of endings and turned into –ed. Class III retained only the verbs se33en, libben, habben – seien, liven, haven.
The system of conjugation was simplified. In the Northern and the Southern dialects verbs took the ending –es in the third person singular. Later this ending spread to other dialects and became the only person ending which survived.
The most characteristic feature of the development of the verb in Milddle English is the development of the analytical forms which goes together with the formation of the system of tenses.
Tense forms which appeared in Middle English

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  Shal + infinitive – Future
  
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  Haven + Participle II – Perfect forms
  
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  Ben + Participle I – Continuous forms (at the end of the period)
  
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  Ben + Participle II – Passive Voice (a new category in Middle English!)
  

Future Tenses – developed from the analytical formation shal + Infinitive (3)
Perfect Tenses – developed from the analytical formation haven + Participle II (1) (ben + Participle II for the verbs of motion)
Continuous Tenses appeared at the end of the period. They developed from the analytical formation ben + Participle I
A new category appeared in Middle English. It was the category of the voice. The forms of the Passive Voice developed from the analytical formation ben + Participle II (2).
As for the other categories of the verbs, the changes were such:
The category of aspect lost its importance and gradually disappeared. 3e before Participle II was changed into y.
The category of mood was preserved.
The categories of person and number remained, but the system of conjugation was simplified, as it has already been mentioned.

5. 
   Phonetic changes in Old, Middle and Modern English.
   

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