"This work is divided into two parts. In this part, we introduce and study the notion of supra soft connectedness based on the notion of supra b-open soft sets and give basic definitions and theorems about it. Further, we introduce the notion of supra b-irresolute soft functions as a generalization to the supra b-continuous soft function and study their properties in detail. Finally, we show that, the surjective supra b-irresolute soft image of supra soft b-connected space is also supra soft b-connected. of P^n mainly for n = 3; 4, containing a prescribed number of lines or having infinitely many lines. In many cases we compute their dimension and describe their irreducible components with maximal dimension."