Step 1

Tener que means to have to.
 It is regular in the imperfect.
  To say you had to or were supposed to,
   use the imperfect.

Tenía que traerlo antes del lunes.
      I had to bring it before Monday.

Tenías que dejarlos pasar.
      You were supposed to let them go through.

No tenía nada que hacer.
      He didn't have anything to do.

Teníamos que cocinar para todos.
      We were supposed to cook for everybody.

Teníais que venir conmigo.
      You guys were supposed to come with me.

Ustedes tenían que barrer el patio.
      You all were supposed to sweep the floor.
       (formal)