New answers tagged irregular-verb
There are more examples, but they are of the same type (etymologically unrelated, as Thorsten Dittmar explained for fehlen/empfehlen): (zurück)weichen (ich wich (zurück)) vs. einweichen (ich weichte ein) (er)ringen (ich (er)rang) vs. beringen (ich beringte) (er)schallen (es (er)scholl) vs. beschallen (ich beschallte) There are also verbs that follow ...
fehlen and empfehlen do not derive from the same base (fehlen). The verb fehlen derives from the old form vælen or vēlen, which means to miss (a target). Empfehlen on the other hand derives from the verb fel(a)han, which means to sow or to entrust. finden and empfinden do derive from finden, that's why they share the same conjugation.
I have a pdf book with over 500 verbs that are conjugated in all present, perfect, prateritum etc... But I don't know if the rules of this website allow us to share contact info. If yes, then I can share it with you through some online medium.
Try this one: List of german verbs
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