PL
In 1877 r. priest John Bosco invent of system preventive. Him constituent parts this: knowledge of the ward during of dialogue; accompany a ward in his exercise; and help a ward during of the advise. System preventive of priest John Bosco non lose nothing in the actuality. His have value likewise today. Him value stand out in so that progress of the ward see in acceptance his and of the dialogue with him and resistance a him demand.