Imperfect preterite indicative of the Latin verb sum ( be ) is very similar to the Spanish; in latin is: eram eras erat Erasmus eratis erant: I was you eras it was we were you were they were. Imperfect indicative future is ero eris erit erimus eritis erunt, of which does not derive our will be, but the way how the future was formed in late latin, namely, with the periphrasis of the verb be: I must be and altering the order: I be - I, which became in will be. I said that copulativos verbs are very irregular in all Indo-European languages because they have been and are very seldom used.
