On the existence of $lambda $-projective splitters

Let D be an R-module over an arbitrary ring R of projective dimension at most 1. We construct an R-module G containing D such that Ext(D, G) = 0 = Ext(G, G). Moreover, we show that if D is llambda -projective over a hereditary ring R, for some infinite cardinal llambda , then G is also llambda -projective.