In this paper, we show that (1) for each QFS-domain L, L is an ωQFS-domain iff L has a countable base for the Scott topology; (2) the Scott-continuous retracts of QFS-domains are QFS- domains; (3) for a quasicontinuous domain L, L is Lawson compact iff L is a finitely generated upper set and for any x1, x2 ∈ L and finite G1, G2 C L with G1 〈〈 x1, G2 〈〈 x2, there is a finite subset F C L such that ↑ x1 x2 G2; (4) L is a QFS-d0main iff L is a quasicontinuous domain and given any finitely many pairs {(Fi, xi) : Fi is finite, xi ∈ L with Fi 〈〈 xi, 1 ≤i ≤n}, there is a quasi-finitely separating function 5 on L such that Fi 〈〈 δ(xi) 〈〈 xi.
The concepts of hypercontinuous posets and generalized completely continuous posets are introduced. It is proved that for a poset P the following three conditions are equivalent:(1) P is hypercontinuous;(2) the dual of P is generalized completely continuous;(3) the normal completion of P is a hypercontinuous lattice. In addition, the relational representation and the intrinsic characterization of hypercontinuous posets are obtained.