We give a simple construction
yielding homology classes in (non-simply-connected) symplectic four-manifolds which
admit infinitely many pairwise non-isotopic symplectic representatives. Examples are
constructed in which the symplectic curves can have arbitrarily large genus. The
examples are built from surface bundles over surfaces and involve only elementary
techniques. As a corollary we see that a blow-up of any simply-connected complex
projective surface contains a connected symplectic surface not isotopic to any
complex curve.