Look at these sentences with venir/tenir in le Passé Simple:
Je la tins de toutes mes forces.I held her with all my strength.
Tu ne revins jamais.You never came back.
Et la pauvre Marie devint la reine du royaume.And the poor Marie became the queen of the kingdom.
Nous vînmes voir Paula quand elle était malade.We came to see Paula when she was sick.
Martin et toi tîntes le voleur par les épaules.Martin and you held the thief by the shoulders.
Terrifiées, elles retinrent leur souffle.Terrified, they held their breath.
To conjugate venir, tenir and derivatives in le Passé Simple, here is what to do:
Keep the first letter! (without -ENIR) + endings: -ins, -ins, -int, -înmes, -întes, -inrent
Et la pauvre Marie devint la reine du royaume.And the poor Marie became the queen of the kingdom. Tu ne revins jamais.You never came back. Terrifiées, elles retinrent leur souffle.Terrified, they held their breath. Je la tins de toutes mes forces.I held her with all my strength. Martin et toi tîntes le voleur par les épaules.Martin and you held the thief by the shoulders. Nous vînmes voir Paula quand elle était malade.We came to see Paula when she was sick. 
