Change one Letter

sin = sip..

sip = nip.....................

nip ...pun

pun = nut............................

nut = tan..

tan = and............................................... ......

and = ant..

ant = tab.................................

tab = tap..

tap = ape.................................

ape = eat..

eat = tap..............

tap = zap.......

zap = ape..........................

ape = age.............