How do you determine what verbs do stem changes?
How do you know, without any notes or materials, which verbs undergo stem changes in the present, preterit, imperfect, condicional, subjunctive, and future??
4 Answers
You just have to memorize them.
Para saberlos sin notas o materiales, tendrías a ser psíquico.
You can't "determine" which verbs are stem changing verbs, you just have to learn them. Fortunately, within the groups of stem changing verbs they do follow patterns that make them easier to memorize.
I don't see how you could do this with no materials. You can use the tool on this site to conjugate verbs. Click on More at the top of this page and then go to conjugation. Simply write in the infinitive of the verb that you want and the tool will conjugate it for you. If you are serious about learning Spanish, you might want to invest in an English/Spanish dictionary. After each verb, it is indicated whether it is a stem-changer or not.
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