Many nouns and adjectives are derived from verbal roots via suffixes and ablaut.
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Strong verbs ablaut the lemma's nucleus to derive the past forms of the verb.
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For Ablaut in a specifically Indo-European context, see Indo-European ablaut.
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Ablaut explains vowel differences between related words of the same language.
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In PIE there were already several possible ablaut sequences in the verb conjugation.
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In strong verbs the irregularity results from ablaut, which changes their root vowels.
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Although the pronouns themselves are dissimilar, ablaut is not likely to be borrowed.
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In PIE, there were already ablaut differences within the paradigms of verbs and nouns.
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The Indo-European verb system is complex and, like the noun, exhibits a system of ablaut.
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More examples
A vowel whose quality or length is changed to indicate linguistic distinctions (such as sing sang sung song)
In linguistics, apophony (also known as ablaut, gradation, alternation, internal modification, stem modification, stem alternation, replacive morphology, stem mutation, internal inflection etc.) is the alternation of sounds within a word that indicates grammatical information (often inflectional).
The substitution of one root vowel for another, thus indicating a corresponding modification of use or meaning; vowel permutation; as, get, gat, and got; sing and song; hang and hung, distinct from the phonetic influence of a succeeding vowel
A vowel change that accompanies a change in grammatical function. Same as "gradation." Sing, sang, and sung.
The change of a vowel into another vowel in the root of a word, with a grammatical function, usually for no visible phonological reason. Also known as vowel gradation. The alternant stems of English 'strong verbs' (sing ~ sang ~ sung, write ~ wrote ~ written, etc.) are examples of ablaut. ...
A change made to a vowel or vowels in a word's stem, in order to indicate grammatical information. In English, an example of an ablaut is the change made to the vowel in the present tense form of the word "drink. ...