Question: is tener a stem changing verb?
Answer: Tener and venir are e>ie stem‐changers that also have an irregular yo form. You may remember that these two verbs were listed with the ‐go verbs under the yo irregulars. That is because the yo form of each of these verbs ends in ‐ go; the rest of the forms, however, follow the e>ie stem‐changing patterns.