German : strong and irregular verbs
1. Strong verbs in German, as in English, are those which form the simple past tense NOT by adding " - te" (-ed) to th stem, but by changing the stem vowel.
2. The past participle may have yet another stem vowel change, or may have the same stem vowel, as either the simple past or the infinitive.
In any case the past participle will END in " -en" and NOT in -(e)t.
eg. singen (sing), sang(sang), gesunged(sung)
finden (find), fand (found), gefunden (found)
3. Each verb will have to be learned separately, but it will clearly be helpful to GROUP together verbs which have the SAME pattern of vowel change.
See also : the list of strong verbs
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