That means whenever we go from Lithium to Beryllium to Boron and so on, whenever we go from left to right, our electron activity increases. And that means this guy, this reaction is more exothermic for fluorine than for lithium. In other words, whenever our fluorine gains electrons, it becomes stable and it loses a lot of energy. On the contrary, whenever this guy gains electrons, the reaction for this guy is endothermic. Because this guy, the lithium in the neutral state is more stable than the anion than lithium minus one. And that's exactly what we mean by electron affinity.