Feathers - Feathers have a complex structure of veins, hooks, and barbules that protect birds from the environment and assist them during flight.
(Feathers - Feathers; have; a complex structure of veins, hooks, and barbules) (barbules; protect; birds; from the environment) (barbules; assist; them; T:during flight)
Feathers - Feathers barbules barbules
have protect assist
a complex structure of veins, hooks, and barbules
birds from the environment
them T:during flight