They will get here to-morrow and then I will tell them.
Llegarán mañana y se lo diré entonces.
I will tell it to as many as (all who) will listen to me.
Lo diré a cuantos quieran oirme.—TOMAYO Y BAUS.
Note.—In case of doubt substitute is going to or wants to for will. If the former keeps the sense, use the future tense; if the latter, use querer.
(a) Shall, denoting simple futurity, is included in the future tense.
I shall not be able to come. Shall you be here?
Yo no podré venir. ¿Estará usted aquí?
Expressing determination on the part of the speaker, shall must be translated by a clause or by deber with the infinitive.
You say he has stolen your bicycle? Well, he shall return it at once.