echo "zero
${o=one
two
three
four
five
${s=six
seven
eight
nine}}
ten
eleven
twelve"
t="thir
four
fif
${s/t}"
sed s/\$/teen/<<<"$t"
for i in twen ${t/u}
do
i+=ty
echo $i
sed s/^/$i\ /<<<"$o"
done
echo one hundred