Complex sentence: Molybdenum-99 spontaneously decays to 99m Tc through beta decay, emitting a electron and a electron antineutrino in the process (99 Mo → 99m Tc + +).
Split into simpler sentences: Molybdenum-99 spontaneously decays to excited states of 99 Tc through beta decay. A electron and a electron antineutrino are emitted in the process (99 Mo → 99m Tc + +).