A lot of times in English we will tell our friends by this time I will have done this, or by the time I am 30 I will have a family, In Spanish we use the Future Perfect Tense to say what will have happened by a certain time or date. For this tense we are going to use the verb haber in its past participle form habré before the verb and change its ending to ado for AR verbs and ido for ER and IR verbs. Here are some examples:
Habrás aprendido a nadar antes de que le doce or You will have learned to swim before you are twelve.
Había Habíamos
Habías Habíais
Había Habían
