b=%w[twen thir for fif six seven eigh nine]
a=%w[ty one two three four five six seven eight nine ten eleven twelve]+b[1,7].map{|$_|sub('o','ou')+"teen"}
puts$<.map{|l|z=[]
k=-1
("%012d"%l).gsub(/.../){n=$&.to_i
n>99&&z<<x=a[n/?d]+" hundred"
n%=?d
n>0&&z<<x=a[n]||b[n/10-2]+"ty "[0,n%10*3]+a[n%10]
x&&z<<%w[billion million thousand][k]if 3>k+=1}
z*" "}
Note that non-ascii characters in the above source code will be escaped (such as \x9f).