It tells you what the paragraph is going to be about.
An F1 hybrid (or filial 1 hybrid) is the first filial generation of offspring of distinctly different parental types. F1 hybrids are used in genetics, and in selective breeding, where it may appear as F1 crossbreed. The term is sometimes written with a subscript, as F1 hybrid.
A âmuscleâ hybrid is an approach that uses the electric motor as extra power, sort of like how a bolt-on turbocharger or supercharger would. Instead of cramming more fuel in, it gives more power without requiring more fuel.