Clipped: 
to cut or cut off with or as if with shears.

Sighing:
to take a deep audible breath (as in weariness or relief). An often involuntary act of sighing especially when expressing an emotion or feeling (such as weariness or relief)

on the back of the wind   

and floats downstream   

till the current ends

and dips his wing

in the orange sun rays

and dares to claim the sky.

But a bird that stalks

down his narrow cage

can seldom see through

his bars of rage

his wings are clipped and   

his feet are tied

so he opens his throat to sing.

The caged bird sings   

with a fearful trill   

of things unknown   

but longed for still   

and his tune is heard   

on the distant hill   

for the caged bird   

sings of freedom.

The free bird thinks of another breeze

and the trade winds soft through the sighing trees

and the fat worms waiting on a dawn bright lawn

and he names the sky his own.

But a caged bird stands on the grave of dreams   

his shadow shouts on a nightmare scream   

his wings are clipped and his feet are tied   

so he opens his throat to sing.

The caged bird sings   

with a fearful trill   

of things unknown   

but longed for still   

and his tune is heard   

on the distant hill   

for the caged bird   

sings of freedom.