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

the person – 3 persons (the first, the second, the third);

the number – 3 numbers ( singular, plural and the remains of the dual number in the first and in the second persons);

the gender – 3 genders (in the 3rd person singular);

the case – 4 cases (Nominative, Genitive, Dative, Accusative).

Demonstrative Pronouns
Demonstrative pronouns se and pes had the categories of number, gender and case (2 numbers – singular and plural, three genders and four or five cases; the Instrumental case was added in the masculine and neuter singular).
OE pes – MnE this
OE se – MnE that or MnE the The definite article developed from the Old English demonstrative pronoun se.
The Verb
All English verbs were divided into 7 classes of strong verbs and 3 classes of weak verbs.All strong verbs had the gradation of the root vowel in the basic forms. Classes of strong verb were distinguished according to the type of the gradation and the nature of the root vowel.Weak verbs formed their basic forms with the help of the dental suffix.
Strong Verbs
Strong Verbs had 4 basic forms: the Infinitive, Past Singular, Past Plural, Participle II. Each form was marked by the ending of its own.
The Infinitive - an
Past Singular - (zero)
Past Plural - on
Participle II - en

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  I – the Infinitive, the Present Tense;
  
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  II – Past Singular (1st, 3rd persons);
  
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  III – Past Plural (+ 2nd person singular and the Subjunctive Mood);
  
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  IV – Participle II.
  

Weak Verbs
Weak Verbs had 3 basic forms: the Infinitive, the Past Tense and Participle II. They formed the Past Tense and Participle II with the help of the dental suffix –d and its variants. There were 3 classes of Weak Verbs in Old English: Class1 - Initially the verbs of this class had the suffix –j which caused the doubling of the final consonant in the position after the short root vowel.Weak verbs of the first class were formed from nouns and adjectives:Dom (n) – dom + jan = deman (v)
Infinitive Past Tense Participle II