Question

Why do birds fly in air easily

Answer 1

 A bird uses its legs to push off the ground into the air. That’s called thrust. It flaps its wings to stay in the air. That’s called lift. When you put thrust and lift together, a bird flies. Its wings also have a curved shape, like an upside-down spoon. This shape helps the air move above and below the wings and keep the bird in the air. Birds’ feathers also help them fly. Air rushes through the feathers, creating more lift. 

Answer 2

Birds have unique physical characteristics.
They are light weighted and have bones which are hollow and filled airsacks

The shape of their wing facilities their flight..

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