Rational curves on Fano threefolds with Gorenstein terminal singularities

We study the spaces of rational curves on Fano threefolds with Gorenstein terminal singularities. We generalize the results regarding Geometric Manin’s Conjecture for smooth Fano threefolds, including the classification of subvarieties with higher a-invariants and Movable Bend-and-Break lemma. We also show Geometric Manin’s Conjecture for some singular del Pezzo threefolds.