Entertainment / Literature / Ablaut: Jacob Grimm's term for the way in which Old English strong verbs formed their preterites by a vowel change. This is also called gradation. An example would be the principal parts of Old English strong verbs such as I sing, I sang, and I sung.
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Entertainment / Literature / Weak Verb: In linguistics, a Germanic verb whose principle parts require the addition of a dental suffix--i.e., typically a /d/ or a /t/. Contrast with a strong verb, one whose linguistic principal parts were fo MORE
Entertainment / Literature / Strong Verb: In Germanic languages, a strong verb is one whose linguistic principal parts were formed by ablaut of the stem vowel, as opposed to a weak verb, which forms its parts by adding a dental suffix such as MORE