Feathers, beak, wings, claws.
Birds can fly because they have feathers that enables them to fly. That, and having hollow bones, being lightweight and flapping their wings to propel them through the air.
How do you say Charateristics?
face
bacteria
peaceful
no tail
this is a good site
A vertebrate has a spine.
solid
liquid
one characteristic is that they have broad leaves
it has no characteristics of any kind