  Formal (mixed) Hodge structures FHS are introduced in such a way that the
Hodge realization of Deligne's 1-motives extends to a realization from Laumon's
1-motives to formal Hodge structures of level 1, providing an equivalence of
categories.
  For the sake of exposition we here confine our study to level 1 mixed Hodge
structures. However, it is conceivable and suitable to consider formal mixed
Hodge structures with arbitrary Hodge numbers: generalizing our definition
herebelow it's not that difficult and we will treat such a matter nextly.
